2435 Clotfelter Road, Bogart, GA 30622 phone/fax 770-725-7938,

President, Integrated Health Technologies Corporation, Inc., Carson City, NV

EMT-First-Responder, Oconee County EMS, Watkinsville, GA

Firefighter and Apparatus Operator, Oconee County Fire and Rescue, Station 7, Bogart, GA

Adjunct Paramedic Instructor, Lanier Technical College, Oakwood, GA

Clinical Associate Professor – Institute of Critical Care Medicine, Rancho Mirage, CA

I hope that every one will find this informative and helpful in your practice. My intention is to provide information in several areas of emergency and critical care that will positively impact everyone’s practice. This manuscript will begin with a little personal information that I hope you will not mind me sharing with you.

I am now 59 years old and have been providing emergency and critical care, principally to small animals (dogs and cats), since a student intern at Iowa State University in 1969. There have been other species including horses, cows, coyotes, birds of various types, gerbils, mice, rats, Guinea pigs, rabbits, deer, snakes, iguanas, turtles, alligators, lions, tigers, and humans. I have been blessed in having had an opportunity to gain training at four veterinary schools and seven medical centers, three of which were Level-I Trauma Centers (Shock Trauma in Baltimore, Henry Ford Hospital in Detroit, and University Hospital at OSU in Columbus Ohio). Where I completed an internship at Colorado State, I had an opportunity to scrub-in on cases with two Mayo Clinic trained general surgeons at Pouder Valley Hospital in Fort Collins, Colorado. They taught me techniques that I have been using and teaching also ever since. One you may have heard of and use yourself is the technique of "flashing" (the temporary loosening of a hemostat on a wide pedicle to ensure a tight ligature). As a surgical resident at (The) Ohio State University I spent 3 months assisting in human surgery with Dr. Bill Knerr, a gifted general surgeon who had been practicing large animal veterinarian in his earlier days. He taught me so much and I thank God I had an opportunity to learn from him and many others throughout my career, as there almost wasn’t a career nor much of a life.....

When I was 7 years old I was out playing with my dog Spot on a summer day. We lived out in the country on a not-so-busy country road. I don’t remember much (as I believe my mind does not let me recall it) but this is what I do remember: We were playing in the road and the next thing I remember is that my dog was hit by a car and laying on the side of the road dying. Somehow he had gotten me out of the road just in time as he took the hit from a moving car. "Is there anyone here that can help save my dog?" my mom told me I had cried. There wasn’t. He died a short time later. This, like so many other things, made a big impact on my life. Life Changing Experiences I call them. I know this may be not the venue to mention it but I feel I must. I am also an active emergency medical technician with our local rescue squad and a fire fighter with the local fire department. From these jobs I see many bad things happen to good people including unexpected death.....

The information presented is on practical readiness and techniques that must be done immediately when critical patients first arrive or when the crisis happens during "routine procedures" at your practice. Procedures, operative techniques, and protocols that have proven to be key in the successful management of common emergency conditions are emphasized. Emergency conditions addressed will include patients presented with difficult breathing, collapse, severe hemorrhage, an acute abdomen, parvovirus like cases, gastric dilation-volvulus, and severe wounds and fractures. Many of the procedures and ideas presented will also be useful in the management of "non-emergency patient" seen in your practice that is compromised by disease processes. An example is the older patient with dental disease that has renal and cardiac compromise that requires anesthesia for dental prophylaxis and the removal of a suspected tooth root abscess. With continuous arterial blood flow Doppler monitoring using a $750.00, easy to use monitor, you will have a beat to beat impression of the patient’s cardiovascular status. Since flow is the most important to monitor (over pressure, pulse oximetry) this provides you with key knowledge on anesthesia depth and influence on the patient’s heart and kidneys. Now with the addition of local anesthesia (lidocaine, bupivicaine and the addition of Neut (Abbott Lab) to keep the injection for stinging) you will be able to manage the pain before it starts. Techniques like this save patients lives and can "make your day" Doing a service like this for your clients and their pets; being able to managed animal’s medical conditions effectively, economically, and with safely will make your day. Come and listen and learn.

That which we can provide first, will have the most impact regarding how the patient ultimately does. Such things as applying that spica newspaper splint to a dog with a midshaft humeral fracture as apposed to putting on a Robert Jones splint made of cotton (the former giving the dog what he needs; stability and pain relief). The latter making the dog more painful and providing him with a "Ball and chain" to wear below the fracture and possibly causing radial nerve injury that will never heal. I have seen a number of these situations unfortunately. The veterinarian’s intentions were good but the dogs suffered irreparable damage and never were able to use the limbs again and amputation typically followed.

Another example is Jake who underwent an emergency surgery for the removal of a foreign body. This required the removal a length of bowel (approx. 50% of the jejunum). The bowel anastomosis that was done with 4-0 PDS and the simple interrupted sutures only had gasped the submucosal slightly. Five days later the dog re-presented with fever, vomiting and a painful abdomen. The bowel anastomosis had broken down and the leak of intestinal contents had caused severe peritonitis. If only the bowel anastomosis had been performed with non-absorbable polypropylene and serosally patched with nearby bowel loops as this has been proven to prevent anastomosis failures. The technique also has been very successful for the management of these breakdowns. Crowe, Serosal Patch: Use in 12 Animals, Vet Surgery 13:29-38, 1984.\

Quality emergency care at a moments notice with what ever you have and wherever you are will save lives and save limbs. This is my goal... to give you information and tools you can use to save lives and save limbs. Just remember the newspaper. Put some in your car or truck. Don’t leave home without it (along with some blankets, towels, and duct tape). Remember non-absorbable closure of the gut, as this is the standard these days and add serosal patching with the risky ones; like patching a tire. These save lives and are not difficult to perform. Throughout the seminar other case examples will be used to provide take home messages regarding these principles, procedures and protocols. Some of the cases were those I have experienced during the last few weeks. They are the freshest in my mind. These cases teach me so much and through my experience conveyed to you will prove beneficial.

READINESS: Staff, Facilities, (OR pre-set up), equipment (headlight), small things like a baby monitor, duct tape, cardboard as backboards, mentally being prepared, etc. Much like firefighting, where the firetruck must be a state of readiness, you have to have your practice in a constant state of readiness.

Keep alert, have drills on assessment, management, support (protocols, guidelines)

Can be stressful but keep smiling. Remember about the Power of Positive Thinking

HOME CARE: Give first aid courses (ABCDE) to owners on discharge or open to the public. Techs and vets may teach these courses. Invite the local newspaper. Reinforce that Prevention is best! For example, Tylenol given to cats, chocolate ingestion, a long stick thrown and the dog pouncing on it that died from an air embolis as a section was removed from the brachicephalic vein. Teach with stuffed toy animals. CPR Course: HAVE YOU TAKEN ONE? Example of a veterinarian in Tennessee that heard me say that.... a few weeks later went and took his tech with him... The next Saturday he had a heart attack and arrested. His tech performed CPR until the medics got there. He made a complete with neuro function recovery; The medics said he would not have made it like without the tech doing such a great job with early CPR! SO GET CERTIFIED IN CPR – THE LIFE YOU SAVE MAY BE YOUR OWN (OR A CLOSE FAMILY MEMBER).

TRANSPORT: Make sure the owners know the shorted route and times you are not there. How to transport to prevent complications.

1. Try to prevent much movement; Place is a position of comfort,
2. 2. If laterally recumbent then tape to back-board, cardboard, section of door, etc. Tape at shoulders, pelvis, neck at Wing of the Atlas, others;
3. Prevent further heat loss by covering with a blanket. Do not re- warm however in most cases as this increases oxygen and glucose needs and causes vasodilatation (not a good thing in a patient that is already volume depleted) and the surface re-warming may also cause burns.
4. Do not move quickly as this can cause a profound vasovagal response;
5. Place in a cardboard box or carrier (prefer cardboard box as is easier to get in and out)

Pillow cases work very well for wild cats. Assume its bad and advise as such

6. "LOAD AND GO" meaning don’t spend any more time than necessary to get transported.

Prehospital Care – Professionally provided in human medicine has been shown to play a significant role in the improvement of outcome. This, on a much smaller scale, has also been shown to play a role in veterinary medicine as well. The development of ambulance services has increased significantly in the last 20 years. These services have also provided a great service of hospital-to-hospital transports.

TELEPHONE CALL: Where the care starts –

TELEPHONE ANSWERING PROTOCOL

"The emergency care starts at the scene; the one answering the phone may save the pets life and the owner giving the first aid is key before any care is given at the hospital"

"Every call should be considered an emergency call until proven otherwise from the toy poodle with the torn toenail that is bleeding to the older cat that now acting weird"

Log every call: The following information should be recorded (ideally through voice recording but can be done by writing all the information (difficult to fully accomplish with every call)

1. Date and time of the call and call identification and phone number (ask could I have you name and number so that incase we accidentally get disconnected I can have to call you back). 2. Pet’s name and Signalment.

3. Chief Concern.

4. Recommendations given and by whom.

5. Were any fees mentioned and if so what.

6. Action caller said they would take (if ETA , amount of time estimated).

7. Person taking the call

Logging keeps you out of trouble and the courts.

Example: a man calls in that his queen cat is perceived as having trouble delivering her kittens and asks for advice. The technician asks the DVM and he says the best option if for me to see the cat. The owner is told to bring the cat in and a $70 emergency fee will be expected to be paid on discharge. The owner says he will watch the cat for further developments... This conversation is documented. Two weeks later a letter arrives from the female owner indicating she is very upset with the clinic because they turned her down when she wanted to have the cat looked at. This, she stated "caused the death of all of her kittens" and being they were from a champion blood line she is demanding a reimbursement of 300.00 per kitten that died. There were 5 kittens (as documented by a photo of them with date on the photo, so she is demanding 1500.00 and she had retained an attorney. The log was reviewed and when it was told to her that the log had indicated that a male party had called at 10:35 AM on the date the cat was having problems and said he would watch her rather than come in as was recommended she dropped the complaint (and the demand for the money)

NOT BREATHING: Ensure unconscious (shake hard), pull tongue, extend head neck, rescue breath, reposition head if not able to get breaths in, give 20 minute, check pulse.

NOT BREATHING AND NO PULSE OR HEART BEAT FELT: Ensure unconsciousness (shake hard), do above for not breathing, after give 2 breaths begin chest compressions, do 30 and give two breaths, give 30 compressions and two breaths, get someone else to drive and continue while transporting (except if a very large dog then stay there unless can transport in a van, enclosed truck, etc. Use foot on the chest and you standing if large dog, and compress using leg muscles

BLEEDING BAD FROM LACERATION – PUNCTURE: Muzzle first (unless pet can not breath trough nose) then apply pressure direct with gloved hand if possible on the wound. Then apply a dressing (using cloth). Apply more but do not remove if bleeding continues. Apply pressure above the laceration – puncture if on a limb. Elevate the bleeding site and transport with site elevated.

POISONING SUSPECTED*: If within ½ hour induce vomiting with hydrogen peroxide and small amt of table salt applied in the front of the mouth, not the back, transport while waiting.

* If is petroleum based or strong acid or base do not induce vomiting. Transport only

Hit By A Car, Attacked by a larger animal. Fallen from some height, Unknown but not moving well, Paralysis, Transport without moving the patient much (on side if OK).

Be careful not to get injured from being bitten or scratched by wrapping the patient up in a blanket or place in a cardboard box.

Concern for puppies or kittens being born, having vomiting or diarrhea, being weak, shivering, acting quite, crying a lot,.... request the owners wrap them up in a towel or blanket to keep them warm and transport them with the mother so all can be examined.

Annie a 2 year old slightly obese G Shepard dog that was spayed three days prior. The owner notices a lump at the area of the incision and calls for directions on what to do. The vet tech said to bring for an exam as this could be serious. An appointment was set up for 1 PM. Alice a 2 year old black Lab had an OHE done 4 days prior and now the owner notices a pink –red fluid leaking from the incision and the incision appears puffy. The vet tech also says to bring the dog in for a check-up. She also recommends to place a towel around the abdomen and not to let Alice jump, run, etc. Ands make sure you help her out of the car carefully. Annie and her owner arrive at the clinic at 12:45 and as Annie jumps out of the car the wound dehisces and intestines fall on the parking lot. The dog gets excited and begins to run. The owner has her on a leash though so the running is limited. so the running is limited. Yet the intestines are injured from the dog stepping on them and the owner is heard out in the parking lot screaming. The veterinarian and tech run out and help Annie into the hospital. They take her immediately to treatment and begin with covering the intestines in saline and lap pads. Alice and her owner arrive shortly thereafter. The dog is helped out of the car and has a towel around her abdomen. She is also escorted to the treatment area. The towel is begun to be removed when it is noticed that some omentum is protruding out of the incision. Saline and a lap pad is added and the towel is re-fixed into place around the abdomen with tape and she is scheduled for surgery after Annie. The owners, both out in the waiting room begin to talk. Annie’s "mother" was upset before the conversation... but now she is furious! Fortunately BOTH dogs recovered from their ordeal...however a law suit was pending the last I knew.

THE TELEPHONE INSTRUCTIONS played a major key to both pet’s management.

It should also be remembered from these two cases that CONTINUOUS CLOSURE with secure knots of polypropylene has been shown to be the most secure abdominal wall closure. (Crowe: Closure of Abdominal Incisions Using a Continuous Polypropylene: Clinical Experience in 550 Dogs and Cats. Vet Surg 7: 74-77, 1978).

The 911 Dalmatian – Example of an airway obstruction managed by a police officer that was taught a K-9 Emergency Course = he removed the ball that had been stuck in the dog’s mouth and did mouth to nose rescue breathing and CPR and the pet made a complete recovery. Results proved that with early intervention even dogs that are pulseless and not breathing (PNB) can make a complete recovery with finger sweep – clearing of the airway, mouth to nose rescue breathing, and chest compressions... and that these skills can be taught to the lay public. Crowe:

ALWAYS begin emergency care with high-concentration oxygen supplementation = the most important emergency procedure to be done when faced with many critical life-threatening emergencies. This is accomplish by high – flow O2: blow-by, hood, igloo, dome, collar, nasal-cannula, nasopharyngeal, nasotracheal, transtracheal, box, cage, bag-valve -mask, anesthesia machine to a mask, human non-rebreathing mask, ET tube placement without lifting the head, placement of a cricothyroid cannula, cricothyroidotomy, and tracheostomy. NOTE: It does not include the use of any currently on the market oxygen cages.

Special Equipment Needed (First piece of equipment that I am asking you to purchase and put to use)is a plastic or metal Y connector – attach to the section of tubing coming from your anesthetic vaporizer before it goes into the anesthetic circle circuit. The tubing attached then each have a clamp on them that can be released or clamped to open or close that arm of the circuit. This allows the anesthetic machine to serve as a source for high-flow oxygen that is needed for most of the supplemental oxygen systems used. This same system is used to supply oxygen to the resuscitator bags (AMBU bags). Using a resuscitator bag rather that the rebreathing bag and the anesthetic circuit for rescue breathing allows one to be right up close to the patient and "feel the breaths" being given better and the pop-off valve does not have to be adjusted periodically. No attention is needed to be placed on the valve with the resuscitator bag system. The plastic Y connectors and clamps can be purchased from several companies. Global Veterinary Products, Jorgensen Laboratories (Y flushing system J282y for $52.50),

Cage 43% 35 minutes, Cat tank 95% 4 min Cage w/ plastic over it 55% 25 min

E Collar w/ plastic over it 85% 1 min. Hood of plastic 90 % 3 min Infant Igloo 90% 3 min

Nasal Cannula (Prongs) 45% 1 min. Nasal Catheter 65% 1 min Bilateral Nasal Catheter 80% 1 min.

Naopharyngeal Catheter 80% 1 min Nasotracheal Catheter 98% 30 seconds, Blow By O2 45 % in 1/2 minute

+ flow rates were 5 and 10 L/min until got to catheters and then only 5 L/.min was used.

The addition a 1 ml syringe barrel as a nozzle allows the flow of oxygen to be directed.

Oxygen BEFORE fluids: This is not a new concept but might surprise you as most of us were never taught this in school. Research has proven that there is less reperfusion injury and "energy washout. In a recent article published in SHOCK pigs suffering from experimentally induced hemorrhagic shock that were given 100% oxygen then partially resuscitated with hetastarch had a 0% mortality compared to those given the same amount of hetastarch but were only allowed to breath room air. This later group had a 71% mortality! Meier J: Hyperoxic ventilation reduces 6 hour mortality after partial fluid resuscitation from hemorrhagic shock. Shock 3:240-247, 2004.

Oxygen for head injury – the most important treatment: According to a 2003 study performed by Geoff Manley MD, Chief of Neurotrauma at Univ. California – San Francisco, involving the induction and study of blunt head injury in pigs; Dr. Manley found that supplemental oxygen reduced cerebral edema and improved histologic scoring and physiologic brain function. He stated "It appears from this head injury model that supplemental oxygen is one of the most important if not the most important treatments that can be done on an emergency basis to limit the secondary injury that occurs following TBI"

Oxygen for the prevention of wound infections: According to several studies, supplemental oxygen (even if only up to 28% from 20%) increases oxygen tension in wounds post-surgically from 0 to 28mm Hg. Whitney, JD, et al: Biol Revs Nursing:3: 206-215, 2001. This has been associated clinically with decreases in surgical wound infections on contaminated surgical cases. In 500 colectomy cases that were divided into two groups; those receiving 80% supplemental oxygen versus those receiving 20% oxygen; the group receiving oxygen had only 13 or 250 cases get wound infections. Those only receiving just the 20% oxygen had 28 of 250 cases that got infection. This is an11.2% infection rate w/o supplemental verses an 5.2 % infection rate in those that were supplemented. (Akla GR, et al: Supplemental perioperative O2 to reduce the incidence of surgical wound infection. Outcomes Research Group. NEJM 342:161-167, 2000

The immediate goals of emergency care are the following (after making the area "ready"):

1. To identify the immediate life-threatening conditions.

2. Provide immediate resuscitation and initiate other stabilization procedures.

3. Provide support and communications to the pet’s owner (from the beginning - provide compassionate care, and consider pain and anxiety as part of the life-threatening condition and address these early)

4. Perform a thorough exam and do ancillary diagnostic procedures as indicated

a. physical

b. routine labs *PCV, TS, Azo stick, glucose, lactate, other labs (CBC, chemistries)

c. trauma radiographs (head to tail) chest technique, other films

d. KEEP ON A BACK BOARD if was trauma related or suspect a hemorrhage

5. In many cases, provide the next step as required in a compassionate way: a. humane euthanasia

a. further communications – client education

(VERY IMPORTANT See Table 1 below)

b. further stabilization, diagnostics, and follow-up care

c. emergency surgery and follow-up care

d. transfer to another facility to provide the next level of care.

(if transporting make sure can do it safely – provide oxygen if needed, etc.)

6. Provide documentation (of the care and the communication)

7. Ready the area and staff for the next immediate life-threatening situation.

THESE 7 STEPS MUST ALWAYS BE ADDRESSED.

Speed of the care is a key to success with all medical or trauma patients:

Speed for the patient, efficiency for the practice, and speed too for the owner!

Goal - reversing the state of shock and tissue hypoxia by improving the delivery of oxygen (O2) and nutrients to the tissues, and to arrest the cause of the shock. This involves the ABC's of emergency medical care (see box)

A – Open the airway (extending the head and neck if needed, providing a trach or cricothyroidotomy if needed; intubating using succinylcholine HCl (0.1 mg/kg IV, IM if can’t get an IV established with mini-cutdown or rapid IO needle placement...begin bag-valve mask ventilation as the tracheotomy or cricothyroidotomy and ET tube is being placed).

Example: Boston Terrier with torn trachea example as described above = cardiac arrest in radiology brought to anesthesia –prep room, BVM w/ 100% O2,. No pulse, Chest Compressions initially then intubated, checked for bilateral lung sounds = none = but O2 going in easily.....severe tracheal tear supposed = cervical approach found trachea OK, parasternotomy found trachea pulled apart cranial to heart = elevated distal end of trachea and intubated, direct cardiac massage.. heart responded began beating slowly = gave atropine and 0.01 ml/kg epinephrine and responded very well. patient began waking up (good sign. Started isoflurane and gave oxymorphone 0.03 ml/kg and ace to color(.1 mg) and continued PPV and observation , ECG, Doppler flow and BP with chest covered while went to discuss case w/owner...... The owner was told of the crisis that occurred and approved the next step (see D)

B- Ensure adequate ventilation (providing Bag Valve Mask Ventilation [Galls 1-800-854-2706] and use of a PEEP valve if needed (pulmonary pathology believed present) Ambu. Attach to oxygen source at 5, 10,15 L/min for infant, pediatric adult resuscitator bags. Alternative = Anesthetic machine BUT you have to play with pop-off valve and this distracts you; A suggestion = use the machine as oxygen source by inserting a Y connector in the line going to the circuit, clamping off the section then going to the circuit then

C. Control hemorrhage with immobilization (forced; taped to board with towels and duct tape) with the board made of plastic, cardboard, wood and applying pressure (direct) and using pressure points (brachial, femoral, other) and applying a counterpressure dressing , torso wrap, and

C. Control pain and hypertension with medication (ketamine 1-2 mg/kg, butorphenol 0.1-.2 mg/kg, acepromazine 0.01-02 mg/kg all in same syringe giving IV or deep IM in epaxial muscle.

C. Control (overcome) significant hypo-tension-perfusion (by providing volume replacement as required, and support of the cardiovascular system (use Doppler Blood Flow Detector [ Ultrasonic Blood Flow Detector Model 811-B, Parks Medical Electronics, Inc., 19460 S W Shaw, Aloha, OR 97007, 1-800-547-6427 (for flow and pressure monitoring early) – tape the probe onto the foot at the location of the palmar arterial arch middle of depression on palmar side of the paw just proximal to the metacarpal pad; Other locations: eye, esophagus (probe taped to an esophageal stethoscope and placed so it is laying over the heart).

In extremis give 0.1 ml epinephrine per 10 lb body wt.. IV or IO or double dose and given IT by injection or better yet, place in the hypertonic saline and hetastarch mixture to effect until flows improved to a "swish, swish that sounds adequate" or a BP measured by cuff of adequate size of 50-60 mm Hg systolic. Don’t overshoot if possible; Give hypertonic saline and hetastarch mixture at 1 ml of 23% and 3 ml of 6% hetastarch per kg body weight or substitute the hetastarch with a similar colloid such as dextran 70, or gelatin per 1-2 kg body weight. Monitor effect which requires a few minutes to see full effect. Repeat every 3-5 minutes until BP is effective enough (~ 60 mmHg systolic in most cases)

Recent experience with 25% albumin (diluted with 6% hetastarch) as "the colloid" for shock therapy has been very positive = giving like the hetastarch alone with the hypertonic saline, to effect. For patients with very low plasma total protein or serum albumin levels the 25% human albumin should be used to increase albumin levels, given slowly if flow and BP is adequate to bring PTP and albumin to 4.5 and 2.0 respectively.

Example: Gus, lab w/ severe peritonitis from intestinal anastomosis leak...a/d in the abdomen, semiconscious, Doppler flow very poor, BP 30, dehydrated, TPP 2.2, Albumin 0.6 = resuscitated with oxygen. Hypertonic saline 1 ml, with hetastarch 3 ml/kg followed by replenishment of the estimated total body albumin deficit (3.0 - alb level = deficit in g/dl and the albumin compartment estimated in dogs of 100 -110 ml/kg, and cats of 70 ml/kg... Gus at 25 Kg ~ 110 x 25 = 2750/ 100 = 27.5 x (3-0.6 = 2.4) = 66 grams... to be given over 24 hrs (but in this case with severe hypoperfusion 4-5 ml (25%) /kg can be given every 30 minutes with crystalloid support as well (8 – 10 ml/kg until flows are good and pressures are at least 50 to 60 mm Hg)

D- Correct anatomical defects caused by the injury that affect function (e.g., repairing the ruptured urinary bladder) before its consequences impart serious life-or limb (locomotion) threatening complications. The final goal is to have a comfortable and functional pet return to their owner. The example introduced above (Boston Terrier with a torn intrathoracic trachea (cause undetermined but head caught in the fence and panic pulling to get out was believed possible) is continued: The dog was taken to surgery where the trachea was rebuilt. Several rings that were pulled apart were removed and the trachea was anastomosed using 3-0 polypropylene on a swaged on thin GI taper-needle. It was a difficult surgery but it was accomplished successfully. A nasotracheal catheter was placed as the ET tube was removed as the dog had some pulmonary edema (believed to be centroneurogenic in origin. The edema resolved a completed recovery ensured!!

D- Perform diagnostics as needed: This often includes radiographs (trauma films) and stat labs (PCV, TS, Azo, Glucose, Lactate, Chemistries, Lytes, Venous O2, CO2, Base deficit,

Quick look ultrasound (FAST = Focused abdominal –sound for trauma). The lateral radiograph is frequently what is obtained first but in some cases the US is done first

1. Before rehydrating and reperfusing the sick parvo pup or the dog with HGE give the dog a large volume enema (warm saline irrigation to rinse out all the foul smelling (endotoxin and bacterial containing) stool. Then there will be less uptake of these during resuscitation. A study in rats with inducted pancreatitis has significantly more survival if given saline enemas (30 ml/kg) compared to the controls... They had less sepsis and less bacterial uptake and endotoxin uptake.

2. Increase GI blood flow with the use of Mg based isotonic solutions as the Mg is a vasodilator and the calcium a vasoconstrictor.

3. Use of acepromazine and N Acetylcysteine also help increase GI and renal blood flow (provided enough volume is on board before hand)

4. Use a partial parenteral nutritional formula during the GI rest phase (FreAmine 3.5% with 5 % dextrose can be given in peripheral vessels for up to 3 days). Use 1 ml/kg/hr. Add B Vitamins these are O2 rad. scavengers as well

5. Use constant rate infusions of hetastarch to keep colloid osmotic pressure up (> 15). Use 1 ml/kg/hr

6. Trickle feeding of nutrients (glucose, glycine, glutamine to increase blood flow to the gut).

E- Everything else: providing supportive care (pain control, anxiety control, nutritional support, respiratory and physical therapy support as needed very early to prevent hypoglycemia yet not so aggressive to cause hyperglycemia. Draw blood for blood glucose and lactate; give 25% glucose IV until blood glucose is near or slightly above normal. Consider oral 25% glucose 0.1-0.3 ml/kg as gets absorbed through membranes.

Pain and anxiety control = K A B (ketamine 1-4 mg/kg, acepromazine 0.01-0.04 mg/kg, Butorphenol 0.1-0.4 mg/kg = given IM (higher doses or IV lower doses. Can also use lidocaine as a local or general analgesic and is also a membrane stabilizer. 1-2 mg/kg then 50 mcg/kg/min; morphine at 0.1 mg/kg frequently use this drug along with acepromazine (Norman Shumway, MD, PhD Stanford University Medical School used the principle of vasodilatation and no pain with mean pressures of 30 and was very successful with the cardiac cases that required surgery...flow much more important than pressure...Q proportional to r (4^th power) = increased Functional Capillary Density = better tissue perfusion even though blood pressure want down

Nutritional Support = feed 20% glucose and water with glutamine added (1000 mg/ cup of the glucose and water) orally as soon as comfortably possible. Placement of a nasoesophageal or nasogastric feeding tube has been very beneficial. Then the mixture is "trickled" in over hours. Begin with MICROENTERAL nutrition at 0.1 ml/kg/hr and gradually increase the amount every few hours. Devey JJ, Crowe DT, Microenteral Nutrition in Current Veterinary Therapy XIII: Gradually introduce solid food as a gruel. Feed the gut and prevent translocation and stimulate the production of secretory IGG and IGM, MALT

Respiratory Support = encourage deep breathing and good tracheal toilet clearing ; coupage, postural drainage, moving also prevents PE and deep vein thrombosis

Physical Therapy Support = Encourage the pet to begin walking as soon as possible. This prevent deep vein thrombosis and the likelihood of throwing a clot. This also helps send them home earlier.

TRIPLE THREAT ANTIBIOTICS: (TAM) TICARCILLIN, AMOXICILLIN, METONIDAZOLE very safe choice!

Provision of sufficient oxygen and glucose to tissues in as short of time possible is the mandatory: Many factors affect oxygen delivery to the cells; however, in general terms O2 delivery depends on the following:

1. O2 being delivered to the alveoli, effective gas exchange, \
2. the presence of sufficient hemoglobin to carry the O2,
3. adequate cardiac output, determined by adequate circulating blood volume, cardiac muscle strength, vascular tone and heart rate producing adequate macrocirculatory flow (through arteries, arterioles, venules and veins).
4. adequate microcirculatory (capillary) flow through the tissues.

"High Priority Resuscitation" that is resuscitation issues involving the critical emergency patient that can not wait which MUST be addressed immediately upon arrival are those aimed at maximizing oxygen delivery. The treatment must be appropriate and must be provided in a timely manner.

GUT RESUSCITATION - A GOAL Research has shown that if cellular hypoxia to the gastrointestinal tract in dogs continues beyond an hour even though global resuscitation appears adequate death from organ dysfunction and sepsis from gastrointestinal bacterial translocation and endotoxin absorption across the gut wall will likely occur a day to several days later (Shoemaker). Irreversible cellular apoptosis (programmed cellular death) may also occur as an aftermath of the cellular stresses secondary to the global gut effects of the injury. The GI tract must be supported with adequate flow. If the peripheral limbs have poor flow the gut will have poor flow. Pale mucus membranes = pale gut and poor flow. A good resuscitation mixture is oxygen blow-by then the infusion if hypertonic saline and a colloid. (hypertonic saline and hetastarch at a 1 to 3 ratio 1 ml 23% NaCl mixed with 3 ml of 6% Hetastarch and given IV as a mixture (dose = up to 5 ml per Kg patient body weight). This decreases ICAM and other adhesion reactions (platelets and red cells with activated WBCs) to cause microemboli.

THEREFORE successful care reiterated requires timely and accurate patient examination, assessment and treatment in proper sequence according to physiologic priorities. Since all three of these components occur simultaneously in the injured, all three are included in the decision making that must performed accurately and in as short of times as possible. One thing that can not be bought is TIME. Therefore the decisions not only have to be accurate but also with expedience.

PAPER WORK – Allow animals to begin getting treatment based on triage that is done at the door (or over the phone). Emergency care starts with the phone call – and use protocols such as exemplified already (oxygen, immobilization, hypertonic saline and hetastarch,

FACILITIES, EQUIPMENT, SUPPLIES - Ideally to be the most ready to handle emergency patients requires an ongoing effort that begins each morning and continues throughout the entire following 24 hours, only to begin again the next morning. Its ONGOING. Supplies and drugs are checked and stocked; and equipment is checked to ensure good working order. All is made ready. When anything is used it is restocked as soon as possible. Organization of each area should continually to be reassessed as the various areas or used. Ergonomic relationships that will save time and provide more effective and efficient use of each area can be life saving and in this author’s experience have played a key role in saving patient’s lives AND decreasing the frustration level of emergency teams working "against the clock" . Areas and ideas of particular concern are the following:

READY AREA: To treat a seriously injured or ill patient urgently in need of immediate care, soon enough to prevent catastrophic consequences, requires the hospital to be maintained in a state of readiness. For efficiency one centralized area for initial assessment and management should be used. Often the best central "ready" area is usually near the operating room, and is ideally the anesthesia induction and surgical prep area. All seriously injured or ill animals are initially examined and treated in this area. This location should be the area where in-patient emergencies are also treated, except for those that occur in the operating room. The operating room must also be equally as equipped for immediate surgery.

OPEN SYSTEM & CHECK LIST: All resuscitation equipment and necessary drugs should be organized in this area. These materials should be packaged or stocked to facilitate ease of location and use. Open shelves and bins with needed items and drugs is ideal as it allows rapid procurement by all staff. Doors and drawers do not have to be opened or labels read in the open system. The use of a daily check-off list of the ready area's equipment and drugs will insure that the area is always prepared. Following any use of the area for patient resuscitation the check list is reviewed again. Any materials needing restocking are then charged to the client involved and the restocking is completed.

CRASH CART: It is suggested that drugs, instruments, and equipment that may have to be shared between the ready area and the operating room should be kept on a mobile "crash cart. Drawers in the cart are organized into Airway, Catheters, Drugs, Instruments (to open the chest and cross-clamp the aorta), Special Items (such as tracheotomy tubes, chest tubes, Heimlich valve, Doppler flow detector, back-up items, etc.)

WALL CHART: A wall chart indicating drug dosages, standard fluid administration volumes/rates, and direct current watt-second defibrillation levels (based on estimated body weights) is recommended.

LIGHTING: The ready area requires good lighting, similar to that required in the operating room. Dual lights that can be directed at divergent angles are especially important for the care of the seriously injured patient. These patients frequently require emergency surgical procedures that demand this availability of good illumination, e.g., venous cutdown and slash tracheostomy. A focusing high-intensity cool beam light (very useful for close/exacting or deep cavity work) and a wider beam reflecting dish light for general full-body illumination are recommended. A back-up emergency flash light system should be readily available in the even electrical power is interrupted. A "Snake Light" is recommended to be stored in the crash cart. A small halogen headlight that can be purchased from a home supply store is also recommended.

KEY EMERGENCY ITEMS: Key items that are mandatory for the care of catastrophic injuries or illnesses include suction, oxygen, laryngoscope, major surgery pack including a curved Mayo scissors and a Balfour retractor. Assorted catheters, suture, sterile towels and drapes, and emergency drugs such as epinephrine, atropine, and lidocaine are required.

MEDICATIONS, FLUIDS, BLOOD, PLASMA, COLLOIDS: Other drugs and biologics such as a first generation cephalosporin, dextran 70 or hetastarch for plasma expansion, plasma and whole blood (or a walking donor program where blood for transfusion that can be collected on an emergency basis), are also key and irreplaceable. The availability of fresh homologous whole blood, in particular, is paramount in the treatment of most catastrophic injuries because severe blood loss is a common problem in the cases. Even in the shock patient (not suffering from severe blood loss), the need for plasma or some other colloid for volume replacement is vital. Recent studies have shown that vascular compartment expansion or replenishment is only short lived if a crystalloid such as lactated Ringers solution (LRS) is used. In less than an hour over 80% of the LRS is no longer in the circulation and instead is found in the interstitium.

The use of oxygen carrying colloids like Oxyglobin for blood volume resuscitation is also recommended when whole blood is not immediately available. In the multiple trauma patient, particularly in those with lung or head injury, and there are many, the over-expansion of the interstitial space, (common with the rapid administration of "one blood volume" with a crystalloid) may be especially damaging.

Increased amounts of interstitial water over normal values, clinically evident as edema, have been associated with higher morbidity and mortality in humans suffering from multiple trauma. This is in contrast to vascular volume replenishment with a colloid and hypertonic saline where only a few percentage points of the material are in the interstitium after 12 hours. Therefore the bottom line tells us that there is no substitute for blood and blood components, such as plasma, in the successful resuscitation of the catastrophic injured patient.

Human Albumin (25%) [ Baxter] is very effective in shock (hypoperfusion) therapy. This is diluted with hetastarch, dextran, Plasmalyte-A , Normosol-R,

In the drug drawer all should be in multiple dose vials or in containers that are easily accessible. A section of foam rubber should line the drawer and holes cut out that hold the bottles on their side with the label on the outside. Next to each bottle a space should be made that holds 2-3 syringes that are loaded with hypodermic needles. Whenever a drug is needed the syringe is used to pull-up the drug from the bottle and it is administered intravenously, intraosseously, transtracheally, intracardiac, or deep intramuscularly in the epaxial muscles.

The following drugs are those needed in emergency situations:

Atropine for bradycardia, vasovagal reflex hypotension, bronchospasm. 0.05 mg/kg

Bicarbonate (sodium) used 1:5 with lidocaine to prevent pain on injection. Used for metabolic acidosis. Consider 1:10 dilution with saline and then use with Lidocaine and bupivicaine 50:50 combination for pain relief as a local block and in thoracic and peritoneal cavities postoperatively. Sodium bicarbonate has also been used to decreased K levels in the serum: 0.5-1 mEq/kg slowly over 2-5 minutes; then infuse an additional 1-2 mEq / kg over 30-60 minutes.

Calcium gluconate or calcium chloride for hypocalcemia and hyperkalemia and anesthetic overdose arrest. For acute hypocalcemia 10% solution, 50-150 mg/kg (0.5-1.5 ml/kg) over 20-30 min. If bradycardia, ST segment elevation of QT interval shortening occurs then stop the infusion. And begin again at a slower rate once the problem resolves. For Cardiac Arrest give 1 ml per 10 kg push, especially if thought to be induced by anesthetic overdose, potassium chloride, or calcium channel blocker injection. Continue CPCR, follow with a flush of saline, other physiological salt solutions not containing magnesium, and monitor results.

Dextrose: For hypoglycemia: To effect 0.25 to 0.5 ml 25% dextrose per kg body weight. Repeat glucose testing after 2-4 minutes; repeat doses as needed.

Epinephrine for cardiac arrest, anaphylaxis, extreme hypotension, severe bradycardia, severe bronchospasm 0.01 ml/kg for extreme hypotension and severe bronchospasm, up to 0.1 ml/kg for cardiac arrest (but do have a defibrillator at this dose as many will go from fine to course fib requiring defibrillation (good results seen with this higher dose of epinephrine if "responds"

Lidocaine for ventricular tachycardia and for local and regional and epidural anesthesia. 1-2 mg/kg (1/2 to 1 ml per 10 kg of 2% solution. Has general anesthesia and analgesic properties as well when used systemically after the loading dose (above) and then 30-60 mcg/kg/min.

NOT recommended as a first line drug for fibrillation or pulse less ventricular tachycardia. .

Methylprednisolone sodium succinate for severe shock, head or spinal cord injury, anaphylaxis, asthma. Up to 30 mg/kg slowly IV push

Diltiazem for malignant hypertension, supraventicular tachycardia. 0.125 – 0.35 mg/kg IV slowly. For atrial tachycardia 0.05-0.15 mg/kg IV slowly and repeat every five minutes until see conversion or until a total dose of 0.3 ml/kg. Cats same doses.

Dopamine for hypotension, splanchnic blood flow support, bradycardia. 2.5 to 15 mcg/kg/min.

Dobutamine for cardiac failure, shock 5 mcg/kg/min. It is a serious positive ionotropic agent. I use it for many septic patients as they often have a decrease in cardiac output

Mannitol for cerebral edema, spinal cord edema, shock. 0.25 to 1 G per Kg

Adenosine for sustained supraventicular tachycardia that does not respond to vagal maneuvers (carotid pressure, ocular pressure), have ECG monitoring ongoing, as Adenosine works by decreasing conduction through the AV node. Therefore pacing should be able to be performed and CPR should be ready to be done. In most cases only a transient heart block is observed after dosing as the action of the drug is short lived. .05 to 0.1 mg/kg IV push, if cardioversion is not seen within 2 minutes the dose can be doubled and repeated. It can be doubled a third time and used if the first two doses do not convert the SVT to a normal rhythm.

Midazolam for severe seizures: 0.06 – 0.2 mg/kg IV

Insulin for hyperkalemia and hyperglycemia. Give 0.1- 0.2 U/kg IV and 2 G (4 ml of 50% dextrose per Kg. This is generally used once serum K levels are > 8. The insulin with glucose and KCl as a GKI solution is used for cases with severe sepsis and energy block. The mixture given is G = 1 gram Glucose (2 ml) per Kg, with 0.1 mEq/L KCl and 0.1 U Insulin per Kg. This mixture has been noted to increase cardiac output in cases that are septic.

Polyvalent antiserum for rattlesnake bite. Give one or two vials slowly IV with pretreatment of patient with diphenhydramine.. One vial or two is the average given IV after the diphenhydramine has been e has been given. There is no question via my experience that antiserum given to dogs is important for their recovery.

Magnesium sulfate or chloride for arrhythmias. Principally used to increase serum magnesium levels,. Severe hypomagnesaemia is associated with neuromuscular fatigue, malignant hyperthermia, and seizure activity. The drug has been used for the treatment of severe bronchiolar spasm, seizures. Using the 25% solution, IV administration provides immediate effects The dose to use depends on the level of hypo magnesium and its current effect. The dose is 5-15 ml over 1-2 hours; or preferred is the dose of 1 mEq/Kg/ day

TICARCILLIN = Very effective against gram negative rod aerobes, especially Pseudomonas. Use with clavulanic acid increases its effectiveness. (Timentin) 40-50 mg/kg q 6-8 hrs IV for sepsis. Protects kidney from overdoses of amikacin

Succinylcholine hydrochloride (depolarizing muscle blocker) .07-0.22 mg/kg dogs. 0.06-0.11 mg/kg cats. Give atropine 0.044 – 0.07 mg/kg prior if at all possible to prevent bardycardia.

Atricurium (nondepolarizing muscle blocker) 0.22 mg/kg initial dose, repeated dose 0.11mg/kg

This is the paralyzing drug I prefer

Acetylcysteine – for increasing GI blood flow including the liver 140 mg/kg dogs and cats, also used for acetaminophen toxicity, after initial dose give ½ this dose every 4 hrs for 6 treatments

Pentobarbital for head injury or seizure control for strychnine seizures give to effect 3-15 mg/kg IV, for status epilepticus in cats and dogs same dose, for sleep to tolerate the ventilator use 1 mg/kg/hr

Phenobarbital for IV Loading for status epilepticus give 3-6 mg/kg as bolus... repeat as needed to control the seizures *(up to 20 mg/kg have been needed in some toxic induced cases). May use as a CRI with diazepam at 2-10 mg/hr

Dexamethasone for glucocorticoid treatment of Addisonian crisis suspected hypotension, given 0.5-1 mg/kg in alcohol form, sodium phosphate form 2-4 mg/kg, status epilepticus adjunctive therapy for secondary encephalitis associated hypoxia 2 mg/kg then 1mg/kg Q6

Dexamethasone in polyethylene glycol (4 mg and 500 mg per ml respectively) is also indicted in head and spinal trauma from the PEG that present. The PEG is neuroprotective from second hit inflammatory mediators, plasma membrane destruction

Hypertonic Saline 23%. used with a 6% colloid 1: 4 for shock with spinal cord, head or lung injury 3 -4 ml/kg as initial loading dose

Oxyglobin as a oxygen carrying colloid for many forms of hypovolemic resuscitation 3 -10 ml/kg (generally giving as goal directed therapy 1-2 ml/kg every few minutes until flow and pressure are adequate. If a threat of still hemorrhaging keep pressure below 70-80 ½ hr

Hetastarch 6% as a colloid for treatment of circulatory volume loss hypotension, for low COP, up to 20ml/kg at one time, but give in 2 ml/kg (cats) and 4 ml/kg (dogs) increments and monitor results. Total daily dose 10-15 ml/kg cats. 20-30 ml/kg dogs.

Plasmalyte A or Normosol R physiologic electrolyte sol. containing Mg & acetate, not Ca or lactate (less cellular apoptosis inducted when Mg rather than Ca ions infused

Fresh Frozen Canine and Feline Plasma for consumptive diseases involving AT3 and clotting factors ands also good for thrombocytopenia as there are platelet fragments in the FFP.

Pooled Canine and Feline Plasma for hypoalbuminemia, not a good source of effective AT3

Whole blood or Packed Red Blood Cells for red cell transfusion needs; 5 ml/kg whole blood, 3 ml/kg packed cells is general initial dose for red cell replenishment, give and recheck PCV, give again same dose every time recheck PCV level, target generally PCV 50% higher than base line up to 30 %. No need in general to go above 30-35%.

Be ready to autotransfuse: Is the ideal blood (if few bubbles and contamination) BUT in some cases this is the only source of compatible cells possible and contamination will be accepted (bacteria, microclots, macroclots). Use a macro filter (170 micron) and if possible a microfilter (20 micron) to clear the clots and micro aggregates that will otherwise contribute to DIC. Consider adding 1 ml CPD A 1 per 10 ml of blood collected to help with the prevention of red cell lysis and injury and microaggregate formation.

Pentoxifylline: a synthetic xanthine derivative, increases red cell flexibility, reduces negative effects of cytokine mediators via its phosphodiesterase inhibition.10 mg/kg Q 12hrs, PO

SPECIAL EQUIPMENT: Effective treatment of serious injuries demands the availability of key equipment that is usually not required for the management of many other conditions. There is also often no substitute, and the lack of this equipment directly jeopardizes the patient's chances for recovery. Key equipment required is listed in the Veterinary Emergency and Critical Care Societies publication Guidelines and Standards of Emergency and Critical Care Facilities in the United States. An example of a key piece of equipment that is required is a suction unit for the evacuation of vomitus, blood clots, thick exudate, or saliva from the pharynx, larynx, and trachea to gain a patent airway. This instrumentation includes: the suction trap bottle, suction tubing, several types of aspirator tips (Yaukauer aspirator tip for pharyngeal aspiration, dental tip for rima glottis and tracheal suctioning, and tracheal-whistle tip-catheters for tracheobronchial tree aspiration), and suction capable of generating up to 300mmHg of vacuum that can be obtained within 4 seconds of clamping the tube. The dental suction tip is used for the aspiration of large pieces of vomitus and clot from the while the whistle tip catheters are used for the aspiration of frothy secretions, vomit, exudate and blood. An endotracheal tube with suction applied to the connecting end can also be used to evacuate particulate debris from the pharynx and upper airway.

Interposition of a suction trap at the base of the dental suction tip or endotracheal tube "suction tip" device will prevent clogging of the latex connecting tubing with large amounts of debris or blood clots. A trap has been described that fits directly onto the endotracheal tube. This allows effective suctioning during the act of intubation and can save valuable seconds. It is recommended that for the "state of readiness" that either a Yaukauer tip, medium sized dental suction tip, or endotracheal tube (with an inflatable cuff) be attached to the suction unit via a 6' section of 5/8" tubing and that the other suction attachments be close at hand so exchange can be done quickly. A section of suction tube with a side hole. This tubing can be used to aspirate the pleural space that is continuously accumulating air or air and blood in spontaneous pneumothorax or trauma cases.

With the newer suction devices all that is required to use it on a chest tube is to just dial the numbers needed. The suction pressure should be limited to 20 cm H20. The PowerVac is the unit I use. The only negative by direct hook up without f[-going through an underwater seal system is that you can not always know if you are actually suctioning free air from the pleural spaced.

ALWAYS USE CONTINUOUS SUCTION (10-20 cm H20) FOR PERSISTANT PNEUMOTHORAX CASES – Provides a means of sealing the leaking lung by keeping it expanded and its surfaces against the chest wall and mediastinum. This provides the physical "vacuum" that draws the leaking surface to other serosal surfaces. Must do for 48 hrs continuously to insure a good fibrin seal. Effective in stopping MOST PLEURAL BLEEDING (works by same method)

Cats with traumatic pneumothorax do very well, in most cases, with the use of a minichest tube made from a 14 g IV catheter 2 ¼ inch with added side-holes made with a no. 15 blade and connected to suction being continued as a constant 20 cm H20 negative pressure via the PowerVac

IMAGING: Maintaining facility readiness in regards to the management of the seriously injured patient applies to the operating room, intensive treatment (care), x-ray, and laboratory areas as well. In some cases the patient may go directly to the OR for resuscitative management. Ideally, effective use of diagnostic radiology requires capabilities for rapid radiograph exposure and development, thus the need of at least a 200 to 300 MA X-ray unit and an automatic film processor. Ultrasound capabilities are paramount for emergency assessment. It has been life-saving in the diagnosis of diaphragmatic hernia, traumatic ventral hernia, necrotizing pancreatitis, liver and splenic mass hematoma and hemorrhage.

OPERATING ROOM - Readiness should also include the operating room "in the ready" where everything should be laid out and ready for the execution of a resuscitative thoracotomy or celiotomy or both as well as cross-clamping of major arterial or venous bleeding sources. Operating room equipment includes suction, good lighting, surgical headlight, sterile instrument pack, lap pads, silicone sheeting, polypropylene on taper needles size 2, 1, 0, 00, 000, 4-0, 5-0, 6-0 and cutting needles size same as the taper sizes. Maxon and Vicryl, and 0, 2-0 silk free ties. 5-0, 6-0, 7-0 polypropylene or polybutester. Special instruments that may be life-saving are various sizes of Satinsky (DeBakey) forceps, Balfour retractors (small, medium, large) and right angle forceps of various sizes. Two to three of each size are needed. Orthopedic wire in the shape of a loop, large 6" sections of tubing 12 and 20 French and umbilical tape are needed to make Rummel tourniquets (a section of Prolene suture or a 3.5 Fr red rubber feeding tube that is pulled through a section of large tubing 14 -18 Fr in the form of a loop that courses around a vessel such as the aorta; a section of wire is used to pull the end of the small feeding tube through after encircling a large vessel; the loop of the smaller feeding tube or Prolene suture can be tightened and a hemostat placed across the tope of the larger tube to hold the loop tight around the vessel it occludes).

SURGERY CAPABILITIES: Because major surgery is often required as part of the resuscitation of patients with catastrophic injury, it is important to have an operating room and the equipment and supplies necessary to perform such surgical procedures that may involve the "acute chest or acute abdomen patient". These are as follows:

* pericardotomy (pericardium can be used as a patch and is very tough)

* aortic cross clamping (done with a curved Kelly & a section of 3.5 – 5 Fr red rubber feeding tube)

* exploratory thoracotomy (with a caudal rib cut at the CC junction a much larger area is exposed)

* lung lobectomy (done with as Miller’s knot of polypropylene, the lobectomy can be done rapidly)

* chest tube thoracostomy (pull the skin forward, place a large bore tube via a controlled opening

* wound exploration and debridement (always recommended on all punctures, all open wounds)

* repair or ligation of major vessel bleeding (most can be ligated, not portal or prehepatic cava)

* tracheal repair and tracheostomy (use interrupted polypropylene, some times continuous)

* exploratory laparotomy with autotransfusion (cut top off of IV bag, pour blood collected, give)

* liver lobe resection (Millers’ knot around the base of the clamps that have crushed the liver lobe

* splenectomy and partial splenectomy (5 clamp splenectomy, ligate below clamp as its flashed)

* intestinal resection and anastomosis (interrupted or simple continuous polypropylene, staples)

* nephrectomy (apply a TA 30 V, or perform dissection and place a Miller’s knot and ligate)

* cystorrhaphy (ventral cystotomy or debride the torn section and close, first place urethral cath.)

* diaphragmatic herniorrhaphy (don’t "try to stabilize" the bad cases before taking to the OR)

LABORATORY: In-house determinations of hematocrit, total serum solids, platelet numbers, white blood cell counts and differential cell counts is a standard requirement. Capabilities for determination of blood glucose, activated coagulation time, blood urea nitrogen, serum electrolytes, blood pH and blood gases and cytologic evaluation of urine, body cavity fluids or lavage samples are life saving in many cases. Hospitals that can't perform these tests should make alternative arrangements e.g., setting up a protocol to have the tests performed at a local human hospital or reference laboratory.

Practical laboratory equipment that should be available includes a microscope and items and chemicals for quick-staining ability Diff-Quick stain, Gram’s stain and methylene blue stain, Snap tests for FeLV and FeIV and heart worm, Centrifuge for urine and blood and hematocrit; hand held electrolyte and blood gas unit such as an I stat, coagulation analysis unit for PT and PTT, rapid slide test chemistry analysis unit such as a Vet-test, incubator and blood agar plates and thioglycolate broth for culture, hemocytometer, and rapid analysis kits for ethylene glycol, parvovirus, and specimen containers for tissues and urine and blood and stool. Dipstick tests for urinalysis, blood in the stool, and others.

PERSONNEL AND MENTAL READINESS: Readiness requires that hospital personnel be mentally and physically prepared. In-hospital training and drill sessions are recommended. Assessment and resuscitation team skills are practiced. When catastrophic traumatic emergencies happen everyone on the staff must know their assignment and be able to perform it well. Drill sessions facilitate the practice of psychomotor skills and working as a team, providing for effective and efficient treatment of critical patients. Ideally at least three experienced professional and technical personnel should be present and involved in the treatment of animals presented following serious injury (polytrauma), particularly chest injury with ventilation compromise. Some of the required technical support can often be provided by receptionists, maintenance workers, or bookkeepers. These individuals can be trained to assist with restraint and to perform basic life support tasks. If an adequate number of professional or paraprofessional members of the team are not present alternatives might include:

1. The enlistment of bystanders or the owner. Although this involves an increased risk of liability and more effort on the doctors part concerning communication and direction for these individuals.

2. Calling other professionals off duty or from another practice. This can work in all but the most catastrophic conditions, especially if an "on - call roster" and agreement is worked out ahead of time and the "response time" is usually under 15 to 20 minutes.

In veterinary medicine logistics play a huge roll in the ability to successfully treat as well often because the manpower and facilities are quite limited and 24-hour care is not possible. Solo practitioners may have to use the owners and family members as part of the team needed to accomplish the care required. The author also has used high school and college students on an "on call bases". This "shock-trauma team" becomes "activated" by a pager system after school, week-ends and holidays after a short training program that includes basic anesthetic monitoring, assisting in surgery, circulating in the operating room, and basic ICU examination and skills. They are placed on call and receive both financial and educational rewards when team members are called in.

Other less optimal methods of providing the help needed to be able to operate a critical trauma case involve using an on-call schedule of the regular employees at the hospital, involving untrained volunteers, or even using the patient's own owners in a crisis situation such as having them sitting on a stool and providing positive pressure ventilation buy manually squeezing an AMBU or resuscitation bag during repair of a diaphragmatic hernia done under intravenous oxymorphone (an opioid agonist) and atricurium (a non-depolarizing muscle blocker). (Note A depolarizing muscle blocking agent such as succinylcholine can also be used to cause rapid physiologic myoneurojunction blockade allowing intubation and uncompromised ventilation) . The suggestion to use owners as part of the "resuscitation teams" is of course not the best. However it does provide at least someone that can assist in a life-or-death situation. There are risks that must be weighed into the decision to involve owners in the care of their own pets in these life-and-death cases however.

Training of the staff can not be overemphasized and a method of training that makes it enjoyable and in which the staff retain much of the information that is taught is to use case based scenarios. Drill sessions in the Ready Area can also be done to hone skills and teamwork. Weekly half-hour service training sessions is also a method of introducing new methods of management and new equipment.

Emergency patients that require definitive body cavity surgery as part of the resuscitation should be managed by a team that includes at least three personnel in the operating room; surgeon, assistant surgeon, and anesthetist - circulating nurse. Ventilator assistance and careful anesthesia monitoring is always required in these patients and having assistance in surgery greatly facilitates intraoperative effectiveness and speed. Provided that mechanical ventilatory assistance is available then one person may be able to function as anesthetist and or circulator. But this is still not ideal

DRILLS: A stuffed toy dog can be used to simulate an "HBC patient" presented in shock and unconscious. Review sessions are held at the conclusion of the drills to evaluate team performance in a positive and constructive manner. These sessions can also be used to introduce and test the feasibility of new treatment protocols

PROTOCOLS: Emergency and critical care protocols for general assessment, management, treatment for specific catastrophic injuries or illnesses are recommended. These protocols should be printed and reviewed at staff meetings. They may also be posted in key areas in the hospital or the "ready" area where they can be referred to easily. They act as guidelines and mental reminders for the staff and clinician in-charge; increasing team efficiency, and helping to prevent assessment and management mistakes.

Each protocol may be organized in a numerical or alphabetical list of steps to follow, or in an algorithm. Protocols should be reviewed and revised as required periodically to insure they remain current, easily understood, and effective in the setting they are used.

The term triage, derived from the French verb trier (meaning to pick or cull) was used originally by French wool traders as they sorted wool into various quality categories. Larrey, a French military surgeon in Napoleon's army used the term triage to identify the act of sorting solders that were injured. His military triage was used to identify those injuries that could be repaired urgently and easily to hasten the solder's return to battle. Although for quite different reasons the system of triage is now used in both human and veterinary medicine for prioritizing care according to urgency in order to save lives and to decrease morbidity.

The act of triage in the management of the emergency patient involves three steps:

1. Preparing for emergency patients ahead of time. This involves identifying an area in the facility where the critical patient will be immediately taken upon arrival, called the Ready Area, and preparing this area as best as possible for the patient's admission.
2. Care of the "incoming patient" with the initial act of assessment and management beginning at the scene of the accident by owners or bystanders. Assessment and care often starts with the answering of the phone by veterinary hospital personnel. If an owner with an injured pet calls the call should be immediately forwarded to a doctor or experience VMT (veterinary medical technician), unless the receptionist has the training to be able to give suggestions for at-the-scene care and transport. .
3. Assessment and sorting of the patient according to the priority of need when the owner and patient arrives at the hospital. As the pet arrives the receptionist immediately announces their arrival by intercom or overhead and a VMT or doctor is immediately summoned to perform 'triage' in the reception area.

The patient is quickly assessed and a brief history is gotten the patient is placed into one of three categories:

Code red: Immediate Life-threatening. Category 1

Code yellow: Emergency but not impending life-threatening. Category 2

Code green: Stable and sure is not life-threatening Category 4

A last category (Code black) is also present. Cases where the owner has elected euthanasia or the pet arrives dead or in extremis. These are generally handled like the red or yellow patients for the sake of the family’s stress they are often going through.

TRIAGE ASSESSMENT: The professional (doctor or veterinary nurse) upon arrival begins assessment by noting the following

Owner and scene—looking for issues of safety, and sense of urgency on owners mind; if it appears safe to go on then the patient is visually assessed from afar...

• LOC (level of consciousness) and AVPU scoring is made (see below)
• Airway patent level by listening for increased or absence of airway sounds
• Breathing rate and effort is determined by watching the chest movements
• Strength and rate of central pulses or heart tones by palpation/auscultation
• Color of mucus membranes and capillary refill time.
• Examination for any outward abnormalities that place the patient in category 1-3 such as active hemorrhage, sucking wounds in the neck or chest or an expanding abdomen.

IMMEDIATE QUESTIONS TO ASK (GAINING PERMISSION TO TREAT): It is recommended to ask owners of code red or blue pets, as the transfer to the ready area is done, if resuscitation can be stated. We commonly ask the question: "can CPR be started if its necessary, Can we start an IV and give oxygen? "

Other questions dictated by the situation me be needed to be asked, in addition, such as "Can we do a tracheotomy as the airway is blocked and its needed to save her life?" or "Can we do immediate surgery to try and stop the bleeding. The risk is high but that is all that we can do?" Can we start a special drug called.. Oxyglobin, Human Albumin, etc.

CRITERIA INDICATING CATEGORY 1 OR CODE RED PATIENTS: Given the economics and logistics involved in most small practices the following is a list of criteria that identify the patient that will need to be operated on an immediate or as near immediate basis to be life-saving in "category one" or "code red" and there is no time for transport to a referral center:

1. Airway obstruction that can not be managed conservatively with endotracheal tube placement and anti-edema therapy. An emergency tracheotomy will be required minimally. If intrathoracic tracheal obstruction is present that can not be relieved a rapid thoracotomy and intubation on the bronchial side of the obstruction will be required. Cardiac arrest is eminent. Open chest CPR will be required if arrest occurs.

2. Increasingly difficult breathing pattern and rising rate despite high-flow oxygen supplementation and a positive thoracentesis with continued blood or air being aspirated continuously via large bore catheter or chest-tube placement. A thoracotomy or parasternotomy will need to be accomplished, source of the air or blood found and controlled and positive-pressure ventilation and volume replacement continued postoperatively.

3. Increasingly difficult breathing pattern despite high-flow oxygen supplementation with a diaphragmatic hernia diagnosed by radiograph or ultrasound. Exploratory midline celiotomy and reduction or the hernia and repair will be required. Other support (respiratory, vascular) also will be required.

4. Cardiac arrest or near arrest with a history of trauma and either increasing respiratory difficulty or shock. This requires a rapid non-prep thoracotomy and aortic cross clamping and CPR. If spontaneous cardiac function is restored then definitive care of the pulmonary, vascular, or pleural space problem will be required.

5. Deepening shock in the face of continuing significant volume replacement. The source of hemorrhage will need to be controlled surgically. This generally means opening the thorax and/or abdomen, cross-clamping the aorta temporarily, finding the source of the hemorrhage, controlling it and then replenishing vascular volume rapidly. Occasionally other areas of hemorrhage are involved including the neck from penetrating trauma; thigh from a closed femoral fracture involving the femoral vessels, or open wounds that are bleeding extensively.

Triage categories can change rapidly. Emergency teams (ideally made up of at least 3 care-givers versed in resuscitation skills and performing in a coordinated effort) should realize the demand placed on frequent reassessments of each patient, especially in the first few hours following injury. All patients should be considered to have a serious life-threatening injury until proven otherwise. Those triaged initially as category 4 or code green, walking in the door without any obvious injury, can and have in my experience be placed into a code red status within minutes due to the rapid development of unresponsiveness due to exsanguination! THEREFORE IT IS HIGHLY RECOMMENDED THAT ALL patients with a history of recent trauma should be admitted to the hospital or sent to a facility where monitoring can be done at least for the next 12-24 hours and where strict confinement can be enforced. My motto is "his spleen is ruptured and continuing to bleed even though he looks like he is a lucky dog"

Safety of the hospital staff (doctors, nurses, and receptionists) during transport and initial evaluation of the emergency patient is very important. Usually the animals are painful and the placement of a muzzle is indicated until the extent of the injuries is known. If the patient has significant facial injuries, or is open-mouth breathing, it may be more appropriate to place a cage type muzzle instead of using gauze or a cloth muzzle which avoids holding the mouth closed. During transport the owner may have been bitten and there may be human blood on the animal. To decrease the risk of transmission of infectious diseases such as hepatitis and HIV, it is strongly recommended that gloves should be worn by doctors and nurses during the initial examination of every trauma patient.

Appropriate treatment of the trauma patient can be instituted only if the patient has been evaluated appropriately. From the time the pet is presented to the hospital to the time it is discharged primary surveys should be performed frequently. In the triage setting the survey should be quickly performed. It always is done the same. At other times it is performed in a slower paced setting. The survey examines breathing effort and respiratory pattern, abnormal body or limb posture, the presence of blood or other materials in or around the patient, and any other gross abnormalities. Level of consciousness as discussed before is assessed along with airway, breathing, and circulation effectiveness. If the animal is unconscious the head and neck should be extended to help provide a clear airway, assuming there are no concerns for a cervical spinal injury. The airway (nose, mouth, pharynx, and trachea) is checked for patency by looking, listening, and feeling. Appropriate precautions always should be taken when examining a patient’s oral cavity and oropharynx to ensure no one is bitten. Fingers should never be placed into the mouth of an agonal patient as this can lead to a serious injury.

The presence of increased respiratory effort, paradoxical chest wall movement, abdominal wall movement with respiration, nasal flare, open mouth, extended head and neck, abducted elbows, and cyanosis are all indicators of respiratory distress which require immediate treatment. Breathing is assessed by watching chest wall motion as well as listening to tracheal and lung sounds bilaterally. It is important to auscult lung sounds bilaterally since the animal may have a significant unilateral pneumothorax or hemothorax. Lung sounds always should be ausculted prior to listening to heart tones since the ear is much less discerning of softer sounds once it has adjusted to louder sounds. Circulation is assessed by checking mucous membrane color and capillary refill time, and ausculting for heart tones at the same time as central (femoral) pulses are palpated. Finally a very rapid assessment and palpation of the abdomen, flank, pelvis, spine and limbs is carried out.

If major abnormalities are noted then treatment is instituted immediately. For example, if the animal is not breathing it should be rapidly intubated and ventilated. Then the remainder of the primary survey is completed. During the primary survey, initial resuscitation of the patient is begun and external hemorrhage is controlled. Direct digital pressure placed on bleeding vessels or areas is the initial resuscitation measure taken and works in the majority of cases. Hemorrhage control will not be discussed in this paper per se. It will be referred to in a subsequent paper presented at this conference).

In the severely traumatized patient it should be assumed that fractures are present until proven otherwise and ideally the patient should be restrained to prevent further injury. Restraint should be minimized if the patient is likely to injure itself further by struggling, if restraint will compromise the airway, breathing or circulation, or if restraint will cause the patient more pain. If there is concern that the patient may injure itself further if it is not restrained it may be appropriate to consider sedating the animal. Laterally recumbent patients or those with spinal injuries can be immobilized effectively by taping the animal to a board using duct tape. Tape is placed over bony prominences to avoid interfering with respiration. Tape can be placed over the rostral aspect of the patient at the level of the wing of the atlas, over the cranial thorax at the level of the scapula and caudally over the wing of the ilium. Backboards made from Plexiglas are useful because not only are they sturdy, but the animal can be visualized on all sides, and radiographs can be taken without having to remove the animal from the board.

Once the primary survey is completed VS (vital signs) data is collected . This includes a thorough history taking session with the owner while staff are collecting VS data. This data includes HR., PR, PS (pulse strength) RR, R E (respiratory effort) (0-3 with 3 being the worst)), BP if possible , Jugular vein distension ability with occlusion, normal is distension visible and noted within 3 seconds, then with relation of pressure on the vein the relation time should be 3 seconds. Temperature by rectal should be avoided if there is any possibility of inducing a vagal nerve response. Cases on record have proven that vagal and sympathetic tone is heightened with respiratory compromised patients and vagal induced cardiac arrest have occurred in cases with hypoxemia, when the patient's rectal temperature was obtained. Information from individuals that had seen the accident will be very contributory to the mechanism of injury. A thorough physical exam should be performed starting again with the airway.. This should be done in the same manner in every patient to ensure no abnormalities are missed. A useful mnemonic as a guide for assessment of all important body systems is A CRASH PLAN.

Visualization, palpation and auscultation are performed as required to assess these:

A Airway It takes a 70 % obstruction = increased sounds. 100% = no sounds.

C Cardiovascular Assess jugular vein distension time, amount, relaxation time

R Respiratory Examine respiratory pattern, rate, effort and auscult all lung fields

A Abdomen Examine each quadrant UR,UL, LR,LL with umbilicus as center

S Spine Palpate spinous processes and assess sensation, movement, and reflexes

H Head Palpate skull, check LOC, pupil light responses, eyes, ears, nose, throat

P Pelvis Palpate pelvis, auscult coxofemora, ROM, do rectal, check genitalia

L Limbs Palpate, check ROM each limb, check color, warmth, sensation of toes,

A Arteries and Veins Palpate brachial and femoral arteries, color of toes, edema

N Nerves Assess sensation and movement of each limb, check skin and pads

A second set of vital signs should be taken and recorded after the secondary survey is completed. This includes respiratory rate and effort, heart rate and rhythm, pulse rate and strength, arterial blood flow and pressure by Doppler, and temperature.

INFRARED THERMOMETRY – A new method of "taking temperature" Requires a small device from Radio-Shack. Others are available as well.

TOE and RECTAL TEMPERATURE – This can also be recorded via a trip to Radio-Shack. Its an indoor and outdoor thermometer.

OTHER DIAGNOSTICS COMMON – ABDOMIONAL and THORACIC ULTRASOUND allows visualization of the diaphragm, often without causing stress because the procedure can be done with the patient setting upright. Do this before DIAGNOSTIC PERITOINEAL LAVAGE,

SERIAL LACTATES, SERIAL PVC,TS, SERIAL VENOUS and ARTERIAL GASES (OXYGEN).

SUGGESTED MINIMUM DIAGNOSTICS (CASES OF POSSIBLE SYSTEMIC INVOLVEMENT)

Primary Survey

Vital Signs (care on rectal temp on difficult breathing cases or those with high vagal tone)

Secondary Survey

Blood Draw (as catheter inserted).PCV, TS, B Glucose, AZO, Lactate (as sentinel) [or V or A Blood Gas]

SUGGESTED DIAGNOSTICS (CASES SHOWING SYSTEMIC INVOLVEMENT)

Primary Survey (and repeat..begin flow sheet)

Vital Signs (care on rectal temp on difficult breathing cases or those with high vagal tone)

Secondary Survey (MAKE SURE TO INCLUDE RECTAL... in sick cases O2 before this)

Blood Draw (as catheter inserted).PCV, TS, B Glucose, AZO, Lactate (as sentinel) [or Blood Gas]

Added Blood Draw (clip jugular vein: establish jugular vein distension time, relaxation time)

Chemistry (including lipase and amylase, bilirubin, liver enzymes, albumin, lytes, venous g

CBC include exam of the slide VD),

Thorax (Lateral and VD) Abdomen (Lateral and VD)

(Trauma Films to include heat to tail lateral views).

(

Ultrasound of abdomen, thorax, possible depending on clinical signs, etc.)

Blood Flow and Pressure as determined by Doppler (Continue to listen to flow)

Toe and rectal temperature differential (Yellow Springs) (Radio Shack) (Fish tank)

Urinalysis and Coagulation Panel, (examine morphology of red cells, platelets, and white cells, and Cytology as required (DPL, other body cavities)

Begin a flow sheet (mark beginning of assessment and treatment times – assign the task for recording if possible

FLOW SHEET --- RESUSCITATION Patients Name _________________________Owner __________________ Date _______

Identified Problem(s) [key reason for emergency treatment-monitoring-emergency] ______________________________________

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TIME______ PROCEDURE OR MEDICATION _______________________ _________ RESPONSE ____________ TEAM MEMBER

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NURSING NOTES Patients Name ____________________________Owner _____________________ Date ______________

TIME______ OBSERVATION- TREATMENT GIVEN_______________________ ________ RESPONSE ____________ TEAM MEMBER

___________ ________________________________________________ ______________________________ ______________

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The goal during resuscitation of all major trauma and medically ill patients is to improve and ideally normalize all physiologic parameters while at the same time providing quality and titrated pain relief. Common initial resuscitative treatment with most major traumatized and severely ill patients include the following steps, beginning with the providing of supplemental high oxygen:

Oxygen (O2) should be provided to all seriously injured or seriously ill patients from the time of admission to the ready area ESPECIALLY if they have any increase in respiratory rate or effort. If there is any question as to severity it is better to provide supplemental oxygen that to withhold it. The physiologic reason for this that a high percentage of major trauma and ill patients have at least some lung ventilation-perfusion mismatching and oxygen supplemented helps prevent some of the hypoxic hypoxia - dysoxia that would otherwise have occurred because of it.

BLOW-BY OXYGEN: can be administered by placing tubing from an O2 tank or tubing via a y connector from the oxygen source of an anesthetic machine (thus by-passing the anesthetic circuit) in front of the patient’s nose and mouth and running high flow rates (3 to 15 liters/min) of O2 via the tubing.

HOOD OXYGEN: Small patients can be placed in clear plastic bags filled with oxygen. Otherwise the bag can be placed over the patient’s head. The O2 tubing is placed through a small hole in the front of the bag thus creating an O2 bag or "tent". The back end of the bag is left open and the examination can be completed with the patient in the bag.

NON-REBREATHING BAG AND MASK: O2 by non-re-breathing face mask will provide up to 95 % oxygen whereas a straight mask will only provide up to 50% oxygen concentration.

CROWE OXYGEN COLLAR: This is done by providing supplemental oxygen by placing plastic wrap over the bottom half of an Elizabethan collar and bringing the supply line into the area under the patients chin and running the rate at 2-6 liters/minute. At least 60-70& oxygen can be provided easily using this system. Occasionally this system leads to increased stress just as placing any E-collar on does. If this occurs sedative drugs may be needed.

NASAL O2 CANNULA: Human nasal cannula (adults, pediatric, or infant) can be used effectively to provide up to 50-60 % or .5-.6 FiO2 (fractional inspirational percentage of oxygen when both cannula are in the nostrils of patients. They can be placed quickly with only the need to place a section of tape on the device to form a nose-band then the apparatus is stapled to the patient's face and the placement.

NASOPHARYNGEAL (NP) OXYGEN CATHETER: This can be used early but is generally used following these other methods of supplementation because of the more time and steps needed to provide HP O2. The nostril is medicated with a few drops of proparacaine or other local anesthetic and a 3.5 Fr to 8 Fr. argyle or red rubber feeding catheter or commercial green PVC nasal catheter is inserted into the ventral nasal meatus and inserted to the level of the lateral canthus of the eyes. The catheter is fixed into this position with suture or staples and humidified (preferred) oxygen is administered at 50-100 ml/kg per minute with ½ liter minimum.

NASOTRACHEAL (NT) OXYGEN CATHETER: In very severe difficult breathing patients the catheter can be continued past the lateral canthus into the trachea after hyperextending the head and timing the advancement inhalation. Aspirating on a syringe connected to the catheter will confirm tracheal placement if air is easily withdrawn. The nasotracheal catheter is secured and oxygen at 50 ml/kg minute.

TRANSTRACHEAL OXYGEN CATHETER: In very severe difficult breathing patients especially those thought to have an upper airway partial obstruction on inhalation as part of the difficulty the placement of a transtracheal catheter can be lifesaving as it decreases the work of breathing substantially. A rapid clip and preparation of the skin of the ventral neck is done and a small nick is done on the midline over the mid section of the trachea with an 11 blade. An inside the needle venous catheter is inserted into the trachea and the catheter advanced to the thoracic inlet. The position inside the lumen of the trachea is verified by aspirating on the catheter and getting a free flow of air. The catheter is secured with a suture that extends into the fascia. A dressing is applied around the neck and the end of the catheter also attached to the bandage. Humidified and warmed (preferred) oxygen is delivered at 50 ml/kg/min. In an emergency any source of oxygen is fine.

OXYGEN CAGE – This form of oxygen supplementation can be used but it’s the least effective. This is based on experimental and clinical research that reveals that oxygen levels only gradually increase after the animal is placed inside the cage and the oxygen is turned to 20 liters per minute. Even if the oxygen cage is pre-filled with oxygen gas once before the anima is placed inside the cage, the animal is only able to receive levels of oxygen barely greater than 25%. The American Heart Association has guidelines for resuscitation that address oxygen concentrations recommended to be given to emergency patients. These guidelines recommend levels greater than 80%. In one study done by Mark Engelhardt and DT Crowe (Comparison of six non-invasive supplemental oxygen techniques in dogs and cats, 10^th IVECCS Proceedings, San Diego, CA, pg 983,2004) the Synder oxygen cage wads only able to achieve 45% oxygen and this required 30 ,minutes to achieve at a flow rate of 15 liters per minute and it achieved 60 % in 45 minutes. This is in comparison to the Crowe Oxygen E-Collar that achieved 70% in 1.5 minutes with a 5 liter per minute rate.

Indications: If airway sounds are heard but the patient is unconscious it is recommended that the patient be intubated. This will prevent aspiration of mucus, blood, or vomitus, and allow artificial ventilation to be performed if is indicated. The patient should be intubated in lateral or sternal recumbency as atraumatically as possible. Remaining lateral is recommended if the patient is lateral is recommended to avoid aspiration risk and a drop in cerebral blood flow which may occur if the head is elevated.

Even if the airway is completely clear (no airway sounds are heard) the patient is unconscious or near unconscious tracheal intubation should also be done to protect the airway and provide airway access for the delivery of positive pressure ventilation with 100 % oxygen and access for tracheal suctioning. A 14 g peripheral intravenous catheter should be inserted prior if it deemed appropriate, i.e., the patient has adequate ventilation and airway patency to allow for the time it takes to secure the catheter. High Flow-by oxygen into the patient’s mouth as the mouth is opened and the tongue pulled forward (if able to be done).

Initial Procedure (Preoxygenation if possible): Prior to intubation the patient is attempted to be ventilated with a bag-valve-mask (AMBU) with an oxygen reservoir. The tongue is extended, the mouth closed on the incisor teeth or an oral- pharyngeal airway is placed first. Small (No. 0-1) commercial OP airways work well in cats and small dogs and those that are brachicephalic. Others with longer noses benefit from the use of a modified syringe case with its end cut off. A large ET tube can also be used as an OP airway when placed so that its cuffed opening is located rostral to the rima glottis and the connector opening is in front (rostral) to the patient’s nose. The OP airway is indicated when the tongue requires forceful depression to provide a patient airway. Lingual and sublingual swelling causing airway compromise is also an indication for the use of an OP airway or ideally simply the insertion of an endotracheal tube into the trachea. OP devices do not take the place of endotracheal tubes and tracheal intubation but are helpful when laryngeal intubation is problematic and the obstruction is limited to the lingual and oral pharyngeal region. Inserting either an OP airway of endotracheal tube requires an unconscious patient without a gag reflex.

After the OP airway is inserted a tight fitting face-mask is placed and multiple breaths with an Ambu bag are given providing 100% oxygen if at all possible.

Mouth to mask rescue breathing can also be performed if no Ambu or anesthetic circuit is available. A rescuer’s mouth is placed on the tube-end opening of the mask and several breaths are given. Prior to delivering the breaths the esophagus is occluded digitally by pushing ventrally on the midline after the trachea is deviated to the right.

Intubation Procedure: After a few breaths are provided (if possible) the trachea is intubated; This is done ideally with a laryngoscope because this leads to less time to accomplish it and less laryngeal manipulation which prevents heightened sympathetic and vagal tone which possibly could lead to serious arrhythmias and hypotension and ventricular asystole. The tip of a curved Macintosh laryngoscope blade is placed so that its tip is in the pre-epiglottis vallecula. A straight bladed Wisconsin laryngoscopic blade can also be used. With this blade the tip is inserted over the top (dorsal) to the epiglottis. Again the laryngoscope is used to minimize laryngeal stimulation which can cause a vagal arrest. Elevating the patient’s head to intubate should be avoided as this lifting may precipitate an arrest if the patient is hypotensive.

If a laryngoscope is not available intubation is done by visualizing as best as possible the larynx and the tip of the tube is used to manipulate and depress the epiglottis and allow tube placement. If visualization can not be done the tube is passed into the larynx blindly using palpation of the pre-laryngeal region and manipulation of the larynx

Suctioning of the Pharynx: Suction of the pharynx is performed as necessary to clear blood and secretions. This can be done using a Yankauer suction tip attached to an electric suction machine. This is ideal. Suction units should be able to generate a vacuum of 300 mm Hg upon occlusion of the tip the suction tip within 1 minute when the tube is clamped, or a flow rate of air through the open tube suction tube of 30 liters per minute. A handheld suction unit (MityVac) also is effective for suctioning small volumes and is far less expensive (only costing $40-45.00). A clear endotracheal tube also can be used as a suction cannula for clearing oropharyngeal secreations, vomit, blood clots, etc. The suction tip is first placed and then activated and suctioning limited to a few seconds at a time and certainly less than 10-15 seconds.

Endotracheal (ET) tubes recommended: Clear polyvinyl chloride endotracheal tubes that have high volume and low pressure cuffs are ideal and are highly recommended as the endotracheal tube of choice in all emergency intubations. Sizes available should range from 3.0 to 11.0 mm OD. Ideally all sizes of tubes should have a syringe to inflate the cuff with air already preloaded with the amount of air needed to mildly inflate the cuff and attached to the tube. It is also recommended to place a piece of plastic IV administration tubing around each tube with a Larks Head knot to be used to secure the tube in place once inserted. This knot provides a way to "lock-on" the plastic "tie" and also allows adjustment of its position easily and quickly.

Auscultation Following Intubation: Following placement of the ET tube in place the cuff is inflated quickly and the tie used to secure the tube buy bringing the ends around the back of the head and tying in a bow. A stethoscope is used to listen BILATERALLY for lung sounds as a breath is provided by Ambu, anesthetic rebreathing bag, oxygen line or rescuer’s breath (last option only recommended under duress conditions) after the ET tube is secured. Lung sound should be heard easily and equally bilaterally if no pathology is present. Auscultation should ALWAYS be done to confirm proper placement of the ET tube. If lung sound are not heard with the giving of breaths (positive pressure ventilations [PPV]) then either the ET tube is in the esophagus, the trachea is not intact, severe pleural space occupancy is present or all lungs are involved in a very severe small airway obstructive condition such as fulminate pneumonia. If only sound are heard on the right hemothorax one common cause is placement of the end of the ET tube too deep and into the right main-stem bronchus. The tube is then pulled out slightly and breaths given again as auscultation is done. Having now bilaterally lung sounds heard confirms this.

Tracheotomy or cricothyroidotomy involves the creation of an opening into the ventral cervical trachea or the cricothyroid membrane and the insertion of a tube through the opening and into the trachea. On an emergency bases the procedures can be thought of as "Surgical Parachutes". Like a real aviation parachute which is needed to save a life in desperate situations, the emergency tracheotomy or cricothyroidotomy and tube placement are also needed for desperate situations. when NOTHING ELSE will or can take their place. The goal of this presentation is to describe the indications, the procedure when doing these as an emergency, and the care required post placement.

Indications: "When you think you may "possibly" need it…you need it!.. DON’T WAIT insert one right away. Broad indications include the following:

1. When endotracheal tube placement can not be performed in a patient with an obstructed or near obstructed airway where the obstruction involves the pharynx, larynx, or rostral portion of the cervical trachea.

2. When it is necessary to assess and treat the bronchi-alveolar (pulmonary) tree such as the delivery of mediations and the aspiration of exudate from the tracheo-bronchial tree.

3. When it is necessary to decrease the dead space and airway resistance which will decrease the work of breathing.

1. When long term airway control and ventilation is necessary

Examples of specific situations where tracheotomy is indicated:

1. Airway obstruction due to rodenticide toxicity and sublingual hematoma formation

major trauma of the face, nose, and head with significant airway compromise.

2. Long term ventilation need e.g., patient with a herniated C3-C4 disc with respiratory paralysis

severe pneumonia such as that caused by aspiration, e g., patient with myasthenia

3. Airway surgery (larynx, palate, trachea) for access during the surgery and postoperatively

4. Severe pulmonary edema (cardiac, non-cardiac) requiring intermittent mechanical, positive end-expiratory pressure ventilation and frequent aspiration of frothy fluid

5. Postoperative recovery in a patient with significant Pickwickian syndrome requiring intermittent mechanical ventilation.

Contraindications: There are actually no absolute contraindications. Relative ones include the lack of staff to watch the patient following the placement of the tracheostomy tube. This must be done 24 hours/ day as obstruction can occur at anytime and without warning; caused by exudates coughed up into the lumen of the tube. Total occlusion can occur suddenly requiring immediate removal of the tube. Another relative contraindication is a coagulopathy. However even in the face of significant bleeding caused by rodenticide toxicity the need for the tracheostomy outweighs this concern for hemorrhage. Staying on the midline reduces the risk for significant hemorrhage.

Procedure: There are five methods and situational settings involving tube placement. The first three are methods explained below are always done in life-threatening situations. The fourth one can be done as an emergency or elective procedure. The fifth is done as an elective method in most cases. They are described below:

A "seconds count dying before your eyes" situation "slash" tracheotomy": If the unconscious and cyanotic patient cannot be intubated due to severe facial, laryngeal trauma, sublingual hematoma or other cause of obstruction an emergent slash tracheotomy should be performed immediately. An emergent tracheotomy is performed when the patient is dying due to the lack of a patent airway. The procedure, which is performed without clipping hair or performing a surgical prep. If hair is very long a few "swipes" with the clippers allows one to visualize the skin and deeper structures easily and might be done. Regardless preparation should only take seconds and certainly much less than 60 seconds.

In the awake patient with severe upper airway compromise a tracheotomy can be performed under local anesthetic IF he/she is coherent enough to react to pain. An awake tracheotomy can also be used in the conscious or stuporous patient that requires positive pressure ventilation. In the hemodynamically or cyanotic unstable patient we will avoid the need for general anesthesia. The head of the patient is lifted up and stretched out and a knife or scissors is used to cut the skin and two hemostats are used to split the "strap muscles" on the midline or near the midline and the trachea is visualized. A transverse cut between two rings is performed and an endotracheal tube or tracheotomy tube is inserted. In a dire emergency without any ET tubes or tracheotomy tubes available the cut end of an IV ADMINISTRATION DRIP CHAMBER can be used to access the airway with the fluid openings widened with a hemostat. An 11 blade is used to penetrate the trachea and make a small transverse opening and the tip of the drip chamber is inserted into the opening. The end of the chamber is secured with tape to prevent dislodgement.

An Ambu bag then attached to the ET tube, tracheotomy tube or end of the drip chamber and IPPV begun with 100 % oxygen. IPPV is provided initially in a rapid rate to treat hypoventilation which is common with emergency conditions requiring tracheotomy. The tracheotomy tube can be made by splitting the endotracheal tube top and bottom and the wings brought around the neck and tied with two pieces of intravenous tubing. A split 4x4 gauze is then used to dress the surgical opening. The tube is NOT sutured to the skin and the skin incision is left open (later to granulate when the tube is no longer needed)

IF the patient is unconscious or rapidly loosing consciousness the patient is placed into dorsal recumbency. A bag of fluids or sandbag is placed behind the neck. If without sufficient assistance duct tape can be used to hold the patient in dorsal recumbent position.

Exam or surgical gloves are donned. An incision is made in the mid-cervical region with scalpel or scissors (taking a wedge of skin out when using a scissors). A scalpel blade, scissors, pair of hemostats, or fingers are used to separate the midline strap muscles on the ventral . The ventral aspect of the trachea is visualized. The ventral aspect of the trachea is cut across its long axis (transversely) approximately 40 % of its diameter with either knife or scissors. In desperate situations when surgical instruments are not available unconventional methods for making the tracheotomy are used. An example is the use of a sewing scissors. After the opening in trachea is made an ET tube is inserted or if already available a modified endotracheal tube (discussed below) is placed into the lumen and the cuff inflated. Positive pressure breathing is then utilized for all patients. Traction sutures are then placed to facilitate tracheotomy tube exchange. The first 1 to 2 tracheal rings cranial to the tracheotomy opening are encircled with a suture and the knot is tied 3-4 cm away to establish a traction loop. Then the first 1 to 2 tracheal rings caudal to the tracheotomy opening are encircled with a suture and the knot also tied 3-4 cm away to establish a traction loop. A plastic tape tab is attached to each loop and identified with an ink or Sharpie pen as the head (H) and chest (C) loops to allow everyone involved with the patient’s tube management to be able to be oriented and be able to open the tracheotomy incision. For tube changes needed least every 8 hours or whenever the tube becomes partially occluded these traction sutures are grasped and pulled slightly up and out. The old tracheotomy tube is then removal and a new one is inserted.

Using a sterile bandage scissors or its substitute a cut is made halfway down the center *(an alternative is to purchase split 4x4 dressings; these are ideal in that there is less chance for fibers to peal free and become lodged in the tracheostomy wound. With each leg of the "pair of pants" placed around to tracheotomy tube the split dressing is laid against the open tracheotomy wound. The traction sutures are kept under top the dressing. Apply triple antibiotic or its substitute to the skin surrounding the ostomy incision site. Care should be taken NOT to get this ointment in the wound itself.

To the wings of the tracheotomy tube. Make them long enough to be able to tie behind the patient’s neck, thus holding the tracheotomy tube in place. BRING THE TIES AROUD THE BACK OF THE NECK and snug them up so that the tracheotomy tube is forced into the tracheotomy incision. . TIE A LOOP OR BOW BEHIND THE NECK This will allow quick removal of the tracheotomy tube should this become necessary.

Resuscitative Cricothyroidotomy: This is done much the same way as the "slash tracheotomy". Gloves are donned after a quick swipe with the clippers and a squirt with Technicare (the only material FDA approved that does not injure wounds or hurt tissues, including neurotissue, and kills 99.99% of all bacteria within 30 seconds, and no water or alcohol are needed for the prep. The trachea and larynx are palpated with the left hand (from dog’s right side if operator is right handed). A No. 15 scalpel (small animals (small dogs and cats) is grasped on the midsection of the blade and pushed into the soft portion of the HARD-SOFT HARD section on the ventral aspect of the larynx. The fingers guard against the blasé making too deep of an entrance into the laryngeal vault. A hemostat is then put in the opening and the tips spread if needed (on small cats and puppies) and then a reasonable sized ET tube is placed through the opening, guided by the hemostat.. The technique is relatively new. Advantages are that the opening through witch the ET tube is placed is larger than that between two tracheal rings. The technique can be done without any added help and it can be done very quickly .(5 seconds). A tracheotomy tube is fashioned from an ET tube (as described above) and it seems to work very well here as well.(see figures). Dressing and tube changes are the same as a trach. Time will tell how they work compared to the regular rapid tracheotomy.

A more than a few seconds "emergent tracheotomy": Time allows for a more thorough prep with the use of a surgical prep scrub soap/solution such as Technicare which contains 3% chlorxylonol that decreases bacterial numbers by 99.99% within 30 seconds. The use of surgical drape is still avoided in most cases. A local anesthetic (1-2% lidocaine with 10:1 addition of sodium bicarbonate solution) maybe infiltrated. The procedure otherwise is then the same as outlined in No.1. A hemostat or scissors can be placed deep to the trachea and slid through the tissues and out to the other side of the wound thus holding the trachea out of the wound to some extent, allowing better visualization of the trachea before cutting the opening. (Figure 8)

A planed "awake tracheotomy: This procedure is used to gain access of the airway for suctioning and ventilation in a patient that requires such and the use of general anesthesia is contraindicated. Examples include cases with severe pneumonia, pulmonary edema, or severe intrapulmonic hemorrhage and contusion in which high per cent oxygen supplementation does not decrease their significant work of breathing clinically. These patients have an intravenous catheter placed and sedation is provided if necessary. As low a dose as possible is used. The authors frequently use butorphenol up to 0.2 mg/kg and a hub of acepromazine (0.08 mg) up to .05 mg/kg and if necessary the addition of ketamine up to 2 mg/kg).

Patients are held in a sitting position with their head held up and back. High flow "blow by" oxygen is provided to their face if a nasal cannula or nasopharyngeal catheter is not already being used to provide supplementation. A full clip and surgical scrub is performed. A head light is donned and a lidocaine-bicarbonate solution is infiltrated as previously discussed. Insure that 0.5-3 ml is also infiltrated into the lumen.

Sterile gloves are donned and the instrument pack opened. Sterile conditions can be maintained in this procedure and it is performed as explained in No. 2. A surgical drape is placed just in front of patient and then clipped to the skin below the proposed tracheotomy site. No other drape is used. The procedure is the same as explained above however more time is used to complete a careful dissection. Gelpi or some other self-retaining retractors are very helpful in maintaining exposure. An alternative is to have an assistant hold the wound open with Miller-Senn or Army-Navy hand retractors.

"Elective tracheotomy" with endotracheal tube already in place in the anesthetized patient: The procedure is commonly done following surgery of the larynx and palate where edema is significant and it is recognized that extubation would not be possible without causing an airway obstruction. In this situation the procedure can be done in an unhurried fashion. The ventral midline of the neck is clipped and prepped. The procedure is done as explained above in No. 3 except the patient is in dorsal recumbency and full drapes are placed. The neck is hyperextended over a sandbag or bag of fluids.

Types of Tubes that can be used as Tracheotomy Tubes: Homemade (Crowe) polyvinylchloride low pressure high volume cuffed endotracheal tube. This tube is made by removing the plastic universal connector, cutting the tubes length to allow the ET tube to just reach the thoracic inlet The tube is then cut sagitally down the center. The cut is made carefully to protect the inflation line leading to the plastic cuff. The connector is reinserted into the split end of the tube. Others include:

Shiley tracheostomy tube (this is a tube w/in a tube w/ obtorator)

Portex PVC commercially made tracheotomy tube

Cook Silastic rubber commercially made tracheotomy tube

Silver (metal) Jackson tracheotomy tube (available from instrument companies)

Rusch tracheal cannula (T shaped)

Elective Awake Tracheotomy Procedure: This procedure (as discussed above) can be done in a matter of minutes (not seconds, as can be done with the emergent ‘slash’ tracheotomy. It steps are repeated here:

1. Sit the patient on the edge of a table, providing blow-by oxygen as required
2. Give the patient as sedative (IV acepromazine 0.1 - 1 mg PRN and IV butrophenol .5 -5 mg; these can be mixed in the same syringe; other neuroleptic combinations can also be given; a small amount of IV ketamine can be included as a third drug (0.1- 1 mg/kg)
3. A headlight is dawned after the surgical kit is opened on a Mayo pr other small stand and an endotracheal tube is selected (chose three with one larger and one smaller than what is believe to be the best based on tracheal palpation).
4. The head and neck are extended and the hair is clipped and a rapid prep of the skin accomplished. Chloroxynolol 3% is an ideal prep agent as it kills 99.9% of all pathogens within 30 seconds. Commercial products are available.
5. Place a local block in the midline midcervical region (1% lidocaine 2-8 ml)
6. Make a ventral midline incision in the mid cervical region over the trachea.
7. The sternohyoideus and thyroideus muscles are separated on the midline until the trachea is visualized. A Gelpi or other self retaining retractor is inserted or an assistant uses hand-held retractors to provide continuous exposure to the trachea.
8. A transverse incision is made between 2 tracheal rings and the tracheostomy tube, commonly begun as an endotracheal tube is inserted. An endotracheal or tracheostomy tube is inserted, the cuff inflated and positive pressure ventilation immediately begun.
9. Two traction sutures are placed around the tracheal rings proximal and distal to the ostomy. The traction sutures are used to help guide the tube into the tracheal lumen when it is replaced following cleaning or if it becomes dislodged.
10. The tube is secured by tying IV administrative tubing to it and then tied behind the patient's neck.
11. A four-by-four gauze square is folded or cut to make a "pair of pants" dressing and this is used to cover the wound. This dressing is changed as required.
12. Suction of the tracheotomy tube is performed as needed, generally done every 8 hours as a minimum. The tracheotomy tube is changed a minimum of once per 24 hours.

Rarely the trachea will be severed or separated by traction and a cervical incision or parasternal approach to the chest and trachea will be necessary on an emergent basis. This is done with a Mayo scissors. The injured trachea is diagnosed by noting poor lung inflation without any increase in resistance when the AMBU or rebreathing bag is squeezed and contents of these bags just "disappearing" After the approach is made and the tracheal injury is found an endotracheal tube is simply inserted and positive pressure ventilation begun. The injury will then be required to be repaired. Polypropylene taper 3-0 sutures are commonly used to perform anastomosis or repair.

The respiratory rate should be recorded and the breathing pattern should be closely observed. It is important to determine the cause of tachypnea which can be an indicator of either lung dysfunction, hypovolemia, or pain. Symmetry of chest movement and the presence of any abdominal component to the breathing pattern should be noted. Abnormalities may indicate rib fracture (s), flail chest, pneumothorax, hemothorax, pulmonary contusions or diaphragmatic hernia. The chest should be ausculted for the presence of breath sounds, areas of dullness, crackles or wheezes in at least 4 quadrants (upper and lower right and left sides). Chest percussion in at least 4 quadrants may help detect areas of dullness suggesting pulmonary contusions, hollow sounds indicating a pneumothorax, or a fluid line indicating a hemothorax.

Diagnostic thoracentesis: This should be performed bilaterally in any patient in which there is concern that the patient has a pneumothorax or a hemothorax. This should be done prior to taking chest radiographs since positioning the patient for radiographs may worsen respiration and may cause the animal to decompensate. Placement of a chest tube is indicated if negative pressure is never achieved during thoracentesis or thoracentesis is required more than twice within 2 to4 hours. Chest tubes should be placed under sedation and local anesthesia rather than general anesthesia unless control of the patient’s ventilation is required.

Arterial and venous blood gases: These can be done easily using a "bed-side blood gas analyzer". One type is the I-STAT. Only a few micro-liters of whole blood are needed for the analysis. Arterial blood gases are used to evaluate oxygenation and thus provide a means of assessing pulmonary function.

Oximeter: If blood gases are not available O2 saturation often can be assessed using a pulse oximeter. Care should be taken to ensure a good pulse signal is being received by the monitor. If the site for placement of the oximeter probe is other than the tongue, shaving the site will improve contact. Pigmented skin should be avoided. Oxygen saturation should be maintained above 92 to 94 percent.

End-tidal Carbon Dioxide: Another monitor is also highly recommended to be used. This is an end-tidal CO2 monitor. It measures the amount of carbon-dioxide at the end of exhalation by means of an infra-red sensor. Normal values are 35-45 mmHg. Values higher than 50 indicate hypoventilation and hypercarbia. Values below 30 indicate hyperventilation or if the values suddenly decrease below 20 this represents a major decrease in CO2 presented to the lung , i.e., a great decrease in cardiac output. Thus the ETCO2 monitor can be very useful in the detection of hypo or hyperventilation and pre cardiovascular failure. The device can also help determine the effectiveness of resuscitation. Research indicates a resting ETCO2 of 12 or less is associated with a poor outcome.

Chest Radiograph: IF the patient can tolerate a DV radiograph of the chest this should be taken. If a lateral can also be taken this should also be done. However at no time should radiographs be done if the patient is stressed by the procedure. Trauma films - lateral films that involved the cervical through the pelvic area are recommended IF the patient can tolerate them without increasing respiratory effort. If a spinal injury is at all suspected these films should be done as soon as possible after "clearing" the ABC part of assessment and resuscitation.

Wright’s Spirometer: This attaches to a tight fitting mask or endotracheal tube and acts like a small wheel that is "spun" by the gases going by in the tube. It is used intermittently to assess tidal and minute volumes.

Providing Positive Pressure Ventilatory Support - If required. Many severely traumatized patients present with pulmonary injury that worsens rapidly during the early phase of resuscitation. Patients with severe pulmonary contusions or ventilatory failure due to muscle weakness from severe shock may not respond to supplemental O2. A decision should be made to intubated and artificially ventilate the patient if cyanosis or respiratory distress do not resolve with the provision of supplemental O2, or if respiratory effort is worsening despite provision of supplemental O2. If arterial blood gases are available positive pressure ventilation should be instituted if the arterial oxygen tension (PaO2) is less than 60 mm Hg with supplemental O2, or the arterial carbon dioxide tension (PaCO2) is greater than 45 to 55 mm Hg. If the clinician feels confident that a pulse oximeter sensor is providing accurate readings, and oxygen saturation is less than 90 to 92% on supplemental oxygen, and there is evidence of respiratory distress, artificial ventilation is indicated.

Emergency medical pulmonary conditions such as cardiac or noncardiac edema and severe pneumonia may also be indications for immediate ventilatory support if oxygen supplementation does not provide significant decreases in ventilatory effort.

Anesthetic agents usually will be required in order to intubate the awake patient who is deemed to need positive pressure ventilatory support. Rapid control of the airway should be the goal since a prolonged induction may be fatal to the patient. Drugs should be chosen with care as these patients are usually hemodynamically unstable and many anesthetic agents depress cardiac function and cause hypotension. Blood pressure should be closely monitored during the administration of any anesthetic agent. Etomidate hydrochloride d ( 0.25 to 2 mg/kg IV) or ketamine hydrochloride e (5 to 10 mg/kg IV) and diazepam f (0.1 to 0.5 mg/kg IV) are ideal for rapid induction. Short acting thiobarbiturates (5 to 10 mg/kg IV) or propofol (3 to 6 mg/kg IV) also can be used. Thiobarbiturates and propofol can cause significant depression of cardiac function and hypotension and should be used with extreme caution; however, they do provide a rapid induction and are preferred over mask induction. They are the drugs of choice in head-injured patients.

A combination of narcotics (oxymorphone hydrochloride h [0.05 to 0.1 mg/kg IV], or fentanyl citrate [0.02 mg/kg IV; 30 to 60 mcg/kg/hr infusion]), in combination with diazepam f (0.2 to 0.5 mg/kg IV), and neuromuscular blockers (atricurium besylate [0.25 mg/kg IV; 0.1 mg/kg redose or 180 to 480 mcg/kg/hr infusion]), provides the safest means of maintaining trauma patients under anesthesia during positive pressure ventilatory support. All anesthetic drugs should be titrated to effect since patients in shock are much less tolerant of anesthetic agents than healthy animals and these doses are only intended as guidelines. In general it is recommended to start at 25 to 50 percent of the dose used in a healthy animal.

The priorities with positive pressure ventilation are to correct hypoxemia by maintaining PaO2 greater than 60 mm Hg and to maintain PaCO2 in the range of 35 to 45 mm Hg. Initially, positive pressure ventilation can be instituted using a manually operated resuscitation or AMBU bag; however, since most of these patients require multiple hours of ventilation therapy while the injured lung tissue heals, mechanical ventilation is preferred. Peak inspiratory pressures should be kept as low as possible (below 20 cm water) to avoid iatrogenic damage to injured lung tissue. The use of positive end expiratory pressure will help decrease inspiratory pressures in the pulmonary injured patient with a high ventilation-perfusion mismatch. Therefore, if peak inspiratory pressures above 20 cm water are required to maintain adequate O2 levels, positive end expiratory pressure should be instituted. Positive end expiratory pressure can be instituted when using an AMBU bag if the AMBU bag is fitted with a valve that regulates expiratory pressure. (Most newer models have one attached.) Positive end expiratory pressure ideally should remain below 10 cm water; however, it should be kept in mind that even 3 to 5 cm water may lower cardiac output by decreasing venous return to the heart. Therefore, it is very important to ensure adequate intravascular volume is maintained, and that BP and urine output are monitored closely. If cardiac contractility is depressed secondary to the trauma positive inotropes may be required. (see below).

Tidal volumes of approximately 10 to 15 ml/kg should be used and the ventilatory rate should be adjusted to maintain the PaCO2 in the desired range. The trauma patient has increased oxygen demands and PaO2 should ideally be maintained in a high normal range (80 to 100 mm Hg minimum). Oxygen toxicity may occur within 6 hours of breathing inspired concentrations of 100 percent O2 and levels should be reduced to below 60 percent as soon as it is feasible. However the inspired O2 concentration never should be reduced prematurely since hypoxia may be fatal.

The decision to provide artificial ventilatory support should not be undertaken lightly. These patients require intensive monitoring and 24 hour care. If a pneumothorax was present prior to starting ventilation therapy then unilateral or bilateral chest tubes will be required rapidly since positive pressure ventilation will worsen the air leak. Trauma patients on ventilators may develop pneumothoraces because the added pressure from the ventilation can rupture injured lung tissue. The lungs should be ausculted bilaterally at least hourly. Any decrease in airway sounds during auscultation of the thorax, any unexplained decrease in PaO2, or any increase in PaCO2, may be an indicator of a pneumothorax and thoracentesis should be performed. If blood gases are not available pulse oximetry and capnometry using an end-tidal CO2 monitor will help evaluate the effectiveness of ventilator therapy.

CPAP: This is Continuous Positive Airway Pressure that is performed in an assistance mode of ventilation in patients that are able to ventilate and are ventilating on their own. As the animal exhales rather than being able to exhale to a resting airway pressure of zero (normal breathing) the animal is only able to exhale to a resting (end-tidal) airway pressure of 5 cm H20 or other positive number. Also with the animal is taking in a breath an external positive pressure is added to the airway and this "assists" with expanding the lung. It can be done either with a tight fitting facemask or via an endotracheal tube. It is used to decrease the work of breathing and increase the patient’s functional residual capacity (FRC) which provides more alveolar surface area for gas exchange. It is indicated with any patient that is determined to have air exchange problems due to pulmonary edema (any cause) and pulmonary contusion/ hemorrhage. It also helps in the mobilization of pulmonary lymphatic fluid. Ideally the patient should remain on this type of breathing for hours to get all the benefits of CPAP (decreased work of breathing (WOB), increased FRC, and mobilization of pulmonary alveolar and interstitial fluid. However it is my experience that even an initial period of 10-20 minutes of CPAP and then repeated multiple times through the day has very positive benefits as well. Patients with rather severe pulmonary edema from either high pressure edema from heart failure or centroneurogenic causes have shown a significant improvement even with only one treatment episode

CPAP is done in several ways but the two most practical methods I have found are:

1. Using a face mask anesthetic circle circuit and rebreathing bag; The dog is mildly sedated if he fights the mask. The mask is connected to the anesthesia circuit and oxygen flow is adjusted to generate pressure in the rebreathing bag. The bag will look distended and every time the animal takes a breath the bag is squeezed slightly to provide positive pressure onto the circuit whenever the breath is taken. During exhalation, because the rebreathing bag is under tension the patient can not exhale completely. Ideally a manometer is in the circuit so pressures can be monitored. End-tidal exhalation pressure should be 5 – 8 cm H2O and during inhalation pressures are 12-17 cm H2O.
2. Using a face mask with an Ambu bag attached and a PEEP (positive end expiratory pressure) valve connected to the exhalation port and set at 10-15 cm H2O; The Ambu bag is connected to an oxygen source at 10 – 15 L/min with a reservoir also attached. Ideally a manometer is also connected inline so that airway pressures can be monitored. Vital Signs Inc., has a very economical manometer. During inhalation the bag is squeezed to assist the patient with the breath. With the exhalation the bag is allowed to re-expand and the patient’s breath escapes out of the exhalation port (impeded slightly by the PEEP valve so that a complete exhalation to 0 cm H2O is not possible. The PEEP valve is adjusted to provide a measured airway pressure of 5 cm H2O.

PEEP: The indications, principles of why it works for edema, and methodology are the same as for CPAP however with PEEP the breath is initiated by the operator or machine and no spontaneous breathing on the patient’s part is occurring. Most patients receiving PEEP are unconscious and not breathing effectively on their own therefore in the vast majority of cases PEEP Is provided via an endotracheal tube that is cuffed and with the use of a ventilator. Of course PEEP can also be achieved with an anesthetic circuit where the pop-off-valve is set to resist exhalation by attaching a section of corrugated anesthetic tubing from the pop-off valve and running it underwater 10 cm. A PEEP valve can also be used on either an anesthetic circuit exhalation port or that of an Ambu bag. Positive pressure breathing is provided then either "by-hand" manually or via a ventilator. Auto PEEP which is a special form of PEEP can also occur when "breath stacking" is done. This is when the rate and volume of the breaths are so fast or large respectively that the volume of air in the lungs can not be fully exhaled. As this volume increases it provides an automatic amount of pressure still present in the lung circuit at the end of exhalation, thus auto PEEP. Mild amount of auto PEEP are good but if these amounts progress, i.e., continuously stack, the pressures slowly rise and this can cause baro trauma and cardiovascular collapse from the decreasing venous return to the heart.

Assessment

Flow-By Oxygen Administration

Emergent Tracheotomy or Rapid Sequence Laryngeal Intubation

Begin Positive Pressure Ventilation for Respiratory Fatigue

Assess Lung Sounds and React as needed à Chest Tube Placement for Pneumothorax

Add PEEP if required for Centro-neurogenic Pulmonary Edema

Radiographic and Blood Gas Assessment, compare with ET CO2 and SaO2 monitors

Provide micronebulization with bronchodilators, aminoglycoside antibiotics, saline, steroids

Incidence: Pneumothorax is a common complication of trauma, and is often the most likely cause of dyspnea in such animals. It is most commonly caused by rupture of alveoli secondary to increase in intrathoracic pressure against a closed glottis. The clinician must bear in mind, however, that pneumothorax can also be caused by direct penetration of the thoracic wall by a sharp object, rib fractures, or rupture of major airways such as the trachea or bronchi. If a major airway has ruptured, pneumothorax will be accompanied or preceded by pneumomediastinum. The absence of pneumomediastinum on thoracic radiographs makes a tear in a major airway very unlikely. Tension pneumothorax following blunt or penetrating trauma is also a common entity following trauma in both dogs and cats. Most begin as unilateral and rapidly progress to bilateral because of the flimsy nature of the intact mediastinum in these species.

Pathophysiology: Generally a tension pneumothorax occurs secondary to injury to the parenchyma of the lung from blunt of penetrating trauma. With either form of injury a one-way valve effect is in operation. Air, leaking from injured bronchi or parenchyma into a closed pleural space, accumulates in the pleural space. Air enters the pleural space during inspiration but it can not leave. Eventually pressure in the pleural space begins to increase to the point of it interfering with venous return. It only requires a few cm. of water pressure to decrease the return a great deal. When venous return is affected the blood begins to pool in the large capacitance veins and shock ensues.

Research has shown that it takes approximately 30 ml/kg body weight of air trapped within the pleural space before clinical signs are evident in laboratory beagles. From clinical experience the amount of air required to be present in the pleural spaced before clinical signs are observed is quite variable. Patients with severe pulmonary contusions do not tolerate as much pleural air accumulation. Small dogs and cats are also believed not to be as tolerable as large working breeds of dogs . Death, due to lack of venous return and effective ventilation can occur within minutes after the onset of clinical signs in severe cases.

Diagnosis: When the trauma patient is presented in severe respiratory distress, diagnostic tests such as radiographs may be impossible to obtain, or may cause the unstable patient to decompensate. In such animals, the clinician must rely on a physical examination diagnosis of pneumothorax. Physical examination abnormalities that may be found in the animal with pneumothorax include:

- tachypnea: rapid, shallow breathing - recruitment of the secondary muscles of respiration

- nasal flare - unwillingness to lie down, especially in lateral recumbency

- inward scalloping of the intercostal muscles on inspiration - barrel chest

- muffled or quiet lung sounds, difficulty ausculting the heart, may be unilateral, but most often bilateral if any time has gone by since start - increased resonance on thoracic percussion

- subcutaneous emphysema in the thoracic region

If the clinician suspects the presence of pneumothorax in an animal in respiratory distress, immediate thoracocentesis should be performed. Even if radiographs to confirm the condition have not yet been obtained. Only if the animal is not having difficulty with breathing should radiographs be attempted to be obtained. If while positioning is being accomplished signs of respiratory difficulty appear this stress of positioning should be stopped immediately. One may consider use of DV views or horizontal beam lateral views (sitting) if any signs appear.

- elevation of the cardiac silhouette off the sternum

- collapse of the lung lobes, especially the caudal lobes

- absence of lung markings in the periphery

- pneumomediastinum may be diagnosed if the great vessels in the cranial mediastinum are outlined by air

From a distance patients suffering from a tension pneumothorax often appear anxious with obvious exaggerated respiratory effort. As signs progress, the main feature observed is the all out effort to breath. The head and neck are extended, pectoral limbs abducted, chest fully expanded and abdominal breathing is noted. Accessory muscles of the face and neck are activated with each attempted inspiration exhibited by observing the commissures of the mouth being retracted with each inspiration. Cyanosis and paleness becomes progressively more evident. As blood pressure falls the animal becomes unconscious and respiratory arrest occurs. The chest appears expanded, mucus membranes ashen, and heart rate becomes very slow preterminally.

Patient's exhibiting the early signs described receive a tentative diagnosis of pneumothorax or tension pneumothorax if upon auscultation lung sounds are diminished either unilaterally of bilaterally. If familiar with normal chest percussion and the sounds generated by it, this diagnostic test can be very helpful in differentiating severe pneumothorax from hemothorax or other acute fluid accumulations within the pleural space. The former providing a hollow, tympanic, resonant sound and the latter providing a dull, higher pitched nonresonant sound.

Palpation of subcutaneous air accumulating in the caudal cervical or general thoracic region, in patient's that are dyspneic, is also a very good indication that a pneumothorax is present. With tension pneumothorax and the accompanying obstruction of venous return, occasionally venous distension, uncommon in shock caused by hemorrhage, is observed in both the jugular and/or femoral veins. Distension of the soft tissues at the thoracic inlet also accompanies the appearance of a fully expanded thoracic cavity.

RESUSCITATION OF THOSE WITH PNEUMOTHORAX THAT ARE CONSCIOUS: Upon observing clinical signs that suggest the possibility of a pneumothorax, thoracentesis is performed to confirm the diagnosis. The procedure should be done with the patient kept in as comfortable position as possible. Heavy restraint is avoided. Supplemental oxygen may be provided by high flow rates (10L/min) delivered through via a mask, bag (hood), or cannula placed near the patient's head (nose), i.e., the "flow - by technique".

Thoracentesis: Thoracentesis should be done bilaterally at the level of the VTH intercostal space at the junction of the upper and middle thirds. It should be done in such a way as to insure that the pleural space is entered and aspirated. It is suggested to place a drop of sterile fluid (saline or 1-2% lidocaine solution) on the hub of an 18 gauge hypodermic needle that will be used to penetrate the pleura after the needle is inserted into the skin. As the needle is advanced and finally enters the pleural space the fluid either moves inward, indicating a simple (normotensive) pneumothorax or normal pleura, or moves outward, indicating a tension pneumothorax. It is important not to accept a mere feeling of popping through the pleura as confirmation that the pleural space was entered. 3 This can lead to dangerous, erroneous conclusions. A tension pneumothorax could be present but if the thoracentesis needle was not in far enough this would lead to a false-negative result. Placing the needle in too far may lead to a false-positive as the lung is aspirated. This may also lead to a small, usually minimal, continued air leak . Once the pleural space has been entered as evidenced by the movement of the fluid at the hub of the needle, the needle is held very steady. If the needle were accidentally moved while in the pleural space it may cause a small laceration or scrape on the lung's surface, leading to a continued air leak.

After the needle is inserted as described, a large syringe, attached by way of an extension-set and three-way stopcock. should be used in an attempt to aspirate air and fluid. The aspiration of air (confirming pneumothorax) and/or blood (confirming hemothorax) should continue if the patient's condition begins to appear to be improving. Caution is advised in using too small and short of hypodermic needle or butterfly needle for the thoracentesis.

Mini-chest Tube: If taping has to be done more that twice to relieve the patient of respiratory distress, no blood is being aspirated, and a vacuum is being able to be reached easily with aspiration then the placement "mini-chest tube" is recommended. These allow easier and safer repeated evacuations of the air in the pleural cavity. Following the injection of local anesthetic a homemade "minichest tube" is made by adding 5 small side holes in a 16 gauge to 5 Fr. clear polyvinylchloride (PVC) feeding tube. The side holes should not involve more than 1/4 the circumference of the tube. The tube is then placed through a 14 gauge needle that is inserted into the pleural space at the VTH intercostal space. It is advanced so that 3 to 5 inches of tubing are inside the pleural space. The needle is then withdrawn and the catheter fixed to the chest wall with sutures that penetrate the fascia NOT just the skin. An extension set and stop cock are attached and a dressing applied with the stopcock extending out the dorsal surface of the body dressing. A commercial PVC or polyurethane thoracentesis catheter can also be used. The 8 Fr. polyurethane "pigtail catheter" (Cook, Inc.), or the "cavity evacuation catheter" (Arrow, Inc.) also work well as minichest tubes and are very easy to insert. Aspiration is performed once every several hours until little air is removed on several tries and the pet remains comfortable without evidence of respiratory difficulty. A 14 g IV 2- 5 inch IV catheter can also be used , adding side holes, and inserting in such a way that the needle is pulled out to be inside the catheter as it is advanced; the needle is pulled out and the tube fixed.

Chest Tube: If the patient does not appear to improve, or much air or blood is aspirated, or a vacuum within the pleural space can not be reached with simple aspiration then a chest tube should be inserted. The size of the tube selected should be approximately the same diameter as the patient's main stem bronchus. 3 Following a complete surgical prep the skin of the chest is pulled forward and held by an assistant. A local block into the 6th and 7th intercostal (IC) nerves, surrounding tissues and pleura is performed. If the animal is anxious a small amount of sedation is provided intravenously (diazepam 0.1 mg/kg, and oxymorphone 0,05 mg/kg) while supplemental oxygen is continued. An incision in the skin and subcutaneous tissue in the center of the 7th IC space. A hemostat is used to gently dissect a small hole into the pleural space. Air is allowed to enter the space to collapse the lung away from the chest wall. A styleted chest tube is then inserted with the stylet pulled back so that it does not project from the tube's tip. The tube is inserted 3 to 8 inches until all 5 side holes are inside the pleural space. Some commercial chest tubes require several side holes to be made so that at least five are present. The skin is then allowed to return back to its normal position, thus forming a shelf of tissue that will act as a seal, preventing air from entering the pleural space. Aspiration is started with a stopcock and syringe or underwater seal and suction apparatus. The tube is fixed in place using a suture inserted into the periostium of the rib and fascia. A sterile dressing is then applied.

Before a body dressing bandage is applied it is recommended to take a radiograph to check on the position of the tube and insure that no kinks have occurred. Supplemental oxygen via a mask, bag, hood/collar, or nasal catheter should be continued and considered a mandatory prerequisite before thoracic radiographs are taken. A very practical means of providing 15 cm H20 of continuous suction on the chest tube can be done by attaching a section of 5/8 inch diameter tubing in which a side hole has been made that will allow enough room air to be aspirated as suction, using a standard suction unit, is continuously applied. Commercially available chest-bottle systems (Cheesebourough Ponds, Inc.) or chest evacuation systems (PleuraVac, Deknatel, Inc.) (Thoravac, Anderson, Inc.) are, however, preferred. Continuous suction over the course of several days is generally effective in the treatment of pneumothorax the is initially persistent without the requirement of surgery. The continued suction is important as it keeps the visceral and parietal surfaces of the pleura in contact with each other thus forming an internal seal over the leaking lung that is injured. If the leak continues or does not show signs of slowing or stopping then a exploratory thoracotomy or parasternotomy/sternotomy will be required and the section of lung leaking resected.

Resuscitation of those with pneumothorax that are unconscious: Trauma patients with tension pneumothorax will require immediate pleural space decompression. The procedure recommended to be used depends on the patient's condition. Those patients that are presented in an unconscious state are first intubated and receive positive pressure ventilation (IPPV). Often a considerable decrease in pulmonary compliance will be noted during the ventilations. Other signs as indicated above will often be noted. The animals following IPPV will become progressively worse rapidly owing to the accumulation of more air within the pleural space. Most will progress to an extreme catastrophic condition (where immediate death is believed eminent) rapidly. In these cases a resuscitative mini thoracotomy through the unclipped and unprepped chest wall is indicated. This allows the air that had been accumulating within the pleural space to escape very rapidly, resulting in immediate relief of pressure within the pleural cavity.

Once the pleural pressure has normalized improvement in cardiac function due to significant improvement in venous return and cardiac filling during diastole will follow. With this improvement noted and the appearance of cardiovascular stabilization, the patient should be taken to the operating room where expansion of the thoracotomy incision is done following the aseptic preparation of the rest of the chest wall.

If the patient continues to deteriorate due to hypotension, hemorrhage in the abdomen and / or chest should be suspected and the chest should immediately be opened and the aorta cross clamped (see thoracic hemorrhage section). If the animal still can not be ventilated effectively due to a massive air-leak in lung, bronchus or thoracic trachea the chest should also be open immediately and the leak found and dealt with as best as possible. This may involve placing a finger in the hole and ventilating or cross-clamping the lung that is leaking badly and ventilating. The immediate goal is to at least stop or slow down the leak temporarily and provide effective ventilation.

Thoracotomy and Lung Repair or Resection: When the chest is opened exploration of the thoracic cavity should be completed in a methodical and thorough manner. The mediastinum should be fenestrated and the opposite side of the thoracic cavity examined as best as possible as well. Bronchial and pulmonary parenchymal air leakage and injury should be controlled and repaired. Very contused lung or that with bruising injury or severe laceration may require removal of the portion of lung involved. Small lacerations may simply be sutured. Closure of lung parenchyma can be done with a continuous closure over a Carmalt forceps using fine monofilament suture on a swaged on fine taper-point needle placement and closure. Stapling equipment that inserts two staggered rows of B-shaped staples (TA 30 to 90, US Surgical, Inc.) can also be used. Following thorough irrigation and seeing no further leakage (no evidence of bubbles) a large bore chest tube is placed and the thoracotomy closed.

Systemic broad spectrum intravenous antibiotic therapy is recommended to be used during the perioperative period, beginning as early in the operation as possible. The chest tube is used to monitor the amount of postoperative air accumulation and to drain it as well as fluid as required. Experience has been surprisingly favorable regarding the management of these catastrophic patients; with most surviving without major complications providing other types of injuries were able to be managed successfully as well. In our hands, the post thoracotomy infection rate in these patients has been similar to that reported in human patients also experiencing an emergent, resuscitative thoracotomy, i.e., less than 5%

Resuscitation of those semiconscious and extremely dyspneic: Immediate open - needle thoracentesis, without the benefit of clipping and prepping of the skin, is initially indicated. The needle should be of large enough bore (18 gauge minimum) to allow rapid decompression of the pleural space. Following initial placement of the needle a hand should be used to stabilize the needle to prevent its dislodgment or movement within the pleural space. A plastic over-the-needle catheter (with an extra side hole added quickly) is preferred over the use of a simple hypodermic needle as it is safer and may be more effective.

As decompression is initiated an extension set is attached to a three-way stopcock and a large syringe can be used to withdraw the pleural air. Most often in patients with severe traumatic brochopulmonary fistulas air will continue to be aspirated without reaching a negative pressure (vacuum) indicating the need for the placement of a large bore chest tube. Again the chest tube diameter should be approximately the same size as the mainstem bronchus. This is to insure that aspiration will be effective in keeping up with the continued leakage of air into the pleural space from major traumatic openings within the lung parenchyma or bronchi. The tube should be placed on the side of the chest believed to be the most affected, following the use of a local anesthetic placed in the subcutaneous tissues, pleura, and associated intercostal nerves. The tube is best connected to an active low negative pressure evacuation system that is continuously running. An underwater seal and 15 to 20 cm negative suction system, as described previously, is commonly used initially. This insures the removal of air as it accumulates within the pleural space, and keeps the lung expanded so that the visceral pleura of the lung remains in contact with the parietal pleura.

Keeping the lung expanded and the pleural surfaces together helps control and stop the leakage of air from most major pulmonary injury sources. The suction drainage is continued for 2 to 4 days following the last of the evidence of leakage (air bubbles arising from the underwater seal). This is done to insure a firm seal has formed and recurrence is unlikely. Although underwater seal and suction drainage also helps to control major air leaks from bronchial injuries it generally is not effective in leading to a permanent seal. Persistent leakage over 24 to 48 hours is an indicator of such an injury. These require a thoracotomy on the side of persistent air accumulation, and repair of the bronchial injury or in some cases lobectomy of the lung lobe involved with the bronchial injury.

Prognosis: Prognosis for most patients with pneumothorax depends on the extent of other injuries, including the extent of pulmonary contusion and hemorrhage. As a single entity, pneumothorax has a good prognosis.

FLAIL CHEST – Minor ones will not need reparative surgery but do often need a chest tube. Severe ones do better having sutures placed around the ribs of the flail segment as will as some stable ribs (while the pneumothorax is still somewhat present. Then the ribs are pulled out and anchored through holes in a section of fiberglass casting material molded to the chest wall. The shell is worn for 4 weeks and then removed. The chest tube is generally only needed for 48 hrs in most cases. Use lidocaine and bupivicaine in the pleural space 50:50 with a very small amt of bicarb (1 ml/10 ml of the lido/bupivicaine mixture = give .3 ml per cat mixed with 2 ml saline. (.1 ml/kg for most dogs) Be aware that this can cause hypotension if volume is poor as it causes vasodilatation to some extent.

Auscultation and palpation: The heart is ausculted for the presence of murmurs and arrhythmias and the intensity of the heart sounds is noted. Dull sounds may indicate severe hypovolemia, pericardial effusion, pneumothorax, hemothorax, or diaphragmatic hernia. Pulses should be palpated centrally (femoral) and peripherally. The strength should be characterized and the presence of pulse deficits noted. Tachycardia (>140 in dogs and >220 in cats signify sympathetic amplification of rate and common causes in the emergency patient are pain, anxiety, hypovolemia or heart failure. In cats just the opposite commonly occurs with the heart failure; with pulses and heart rate being 140 to 170. Pulse strength that feels weaker than normal or "thready" signifies a narrow pulse pressure which is commonly caused by pain or hypovolemia. It can also be caused by pump failure.

Jugular Distension and Relaxation Time and JVD Amount; Jugular veins should be clipped and checked for distention since this can provide an estimate of central venous pressure (CVP). The presence of jugular distention in trauma patients in shock is most likely an indicator of increased intrathoracic pressure. In the previously healthy animal this may indicate a pneumothorax or pericardial tamponade. If the animal has underlying heart disease jugular distention can be associated with right heart failure. Jugular distention time and relaxation time also should be noted since they may provide an estimation of CVP. Normal JVD Time should be 3-4 seconds (that is the length of time in seconds from the time digital occlusion of the jugular vein is performed to the time the vein is fully distended. JV Relaxation Time normally is between 1 and 2 seconds. Greater than 2- 3 seconds indicates a delay in venous outflow in the cranial vena cava. This is common with heart failure, pericardial tamponade, tension pneumothorax, or heart base tumors. A jugular vein that remains flat and cannot be raised with digital pressure at the thoracic inlet is consistent with significantly decreased CVP and in most cases represents significant volume depletion (either relative or definitive).

Membrane color and refill time: Mucous membrane color and capillary refill time should be recorded. Normal color is pink. Red indicates vasodilation. Pale indicates vasoconstriction. There are many causes for each. In the emergency patient sepsis and endotoxemia should be thought of as the primary causes of the former and hypovolemia and pain as the principle causes in the later. Normal refill times are between 2-3 seconds. More rapid and more slow times are associated with hyperdynamic and hypodynamic causes respectively. These commonly include septic and endotoxemia in the former and hypovolemic shock and pain in the later.

Toe web temperature: Toe web temperature should be taken and compared with the rectal temperature. Toe web temperature is taken by placing a thermometer between a digital pad and the metacarpal/metatarsal pad. A difference of greater than seven degrees Fahrenheit is strongly suggestive of poor peripheral perfusion. Research by Kolata has revealed that a delta T greater than 7 degrees is associated with a decrease in cardiac output below adequate perfusion of tissues. Clinical research has also shown that toe-temperature is a better indication of peripheral perfusion that capillary refill time.

Doppler detected blood flow: This is a mandatory monitoring parameter that must be observed throughout the assessment and resuscitation phase in each trauma patient if at all possible. In my opinion flow assessment is much more important than blood pressure assessment. It can be easily done by clipping the hair off the palmar arterial arch and then taping a 9 mm flow piezo-electric crystal probe to the foot in this location. The unit is turned on and arterial flow is assessed by auditory means; amount of flow during systole based on loudness, strength of the upstroke of each cardiac contraction based on sound during the early portion of systole, and heart rate. The Doppler flow detector can also be used to interrogate the aorta in the unconscious pet by taping the probe to an esophageal stethoscope. Flow through the jugular vein can also be assessed by using the Doppler unit. Throughout the admission and resuscitation phase blood flow is monitored. The sound of the blood flowing by the sensor provides a beat by beat monitoring tool that I have found second to none If the sound gets weaker this generally indicates less flow and therefore less perfusion. If the flow gets louder the opposite is assumed. Heart rate is also detected by listening to the Doppler flows. It is an invaluable tool in monitoring during phases of care that are critical such as in the immediate admission period, during anesthesia, postoperatively in recovery, and anytime resuscitation is being accomplished.

Blood Pressure: Ideally arterial blood pressure (BP) should be measured during the secondary survey as one of the patient’s vital signs, since knowledge of the patient’s BP is very important during resuscitation. Baroreceptors are stimulated in hypotensive patients which causes the heart rate to rise. Knowledge of the heart rate and the BP can help guide fluid resuscitation. (Table 2) There is a wide range of reported normal BP for dogs and cats. In the authors’ opinion patients who present in shock should be resuscitated to a systolic BP between 110 to 130 mm Hg and a diastolic BP between 60 to 80 mm Hg. IF NO EVIDENCE OF HEMORRHAGE IS PRESENT. Mean arterial pressure (MAP) should be maintained above 60 mm Hg to ensure renal perfusion in these cases. Mean arterial pressure can be calculated only if both systolic and diastolic BP are measured using the following formula:

MAP = diastolic BP + (systolic BP - diastolic BP)/ 3

Blood pressure can be recorded directly or indirectly. Direct BP measurement is the most accurate but requires placement of an arterial catheter which often is not practical in the emergency setting. Indirect BP measurements can be recorded using a Doppler ultrasonic flow detector, oscillometric device or a photodetector. Doppler flow detectors are preferred over oscillometric and photodetector devices since they also allow the clinician to assess flow to the periphery of the limb to which the ultrasonic flow probe is attached. Frequently irregular heart beats such as premature ventricular contractions can be detected using a Doppler ultrasonic flow detector.

Recent data suggests that diastolic BP can be consistently measured using a Doppler flow detector. (Devey) Digital palpation of femoral or peripheral arteries may not provide an adequate assessment of BP. The ability to detect pulses depends on the degree of vasoconstriction, pulse pressure (difference between systolic and diastolic BP), and skill of the clinician. During a recent study more experienced clinicians were able to determine femoral pulses down to a systolic BP as low as 30 mm Hg.

Clinical use of an indwelling 3 Fr 15 cm polyurethane catheter (Cook Veterinary Products) placed within the cranial tibial artery for the measurement of arterial pressure and the procurement of blood gases. The technique is not difficult in dogs greater than 20 kg in size. A small cutdown is first performed to allow visualization of the artery. A curved hemostat is then used to help elevate the vessel and then, using the Seldinger Wire technique, the catheter is inserted.

IF HEMORRHAGE IS SUSPECTED then the blood pressure accepted is 30 to 40 degrees below the cutoff provided for both systolic and diastolic. This is to provide an amount of hypotension that might be helpful in decreasing or arresting blood loss yet not so low as place renal or gastrointestinal cells in jeopardy.

Central Venous Pressure; Central venous pressure monitoring can be measured but question has come recently as to its accuracy in determining blood volume. Ideally a jugular catheter should be placed, although a rear limb catheter that extends into the abdominal vena cava may provide accurate measurements. (Machon) In medium and large dogs commercial catheters are not long enough to reach the abdominal vena cava. In this case a long feeding tube can be placed through a 16 or 14 gauge peripheral catheter. A 2 inch 14 gauge of 16 gauge over the needle catheter is inserted and the stylet is withdrawn. A 3 Fr or 5 Fr feeding tube respectively, is fed through the catheter to the premeasured distance. The catheter is withdrawn from the limb and the feeding tube is sutured in place and covered with a sterile dressing. The use of abdominal vena cava measurements has not been validated in trauma patients. Central venous pressure can be measured using an electronic transducer or a water manometer. It also can be estimated using an intravenous fluid bag attached to the central catheter The bag is simply lowered until the drips stop dripping in the chamber. The fluid line can be used as the "monometer".

Assuming no intrathoracic pathology, CVP is a reflection of preload or venous volume returning to the heart. However since much resistance is in small IV lines it has been shown to be inaccurate at times. Since adequate cardiac output depends in part on preload, CVP should be monitored as a guide to fluid therapy. Although normal CVP is reported to vary from between 0 and 10 cm of water, the goal during resuscitation should be to maintain the CVP between approximately 5 to 8 cm water provided active hemorrhage is not anticipated or known to be present. If active hemorrhage is of concern then CVP from 1-3 is aimed for. Measurements of CVP are affected by the pressure within the cavity in which the tip of the catheter is located. For example a pneumothorax will raise intrathoracic CVP, and increased intraabdominal pressure from bleeding may raise intraabdominal CVP.

Electrocardiograph Monitoring: A lead two rhythm strip is taken and if abnormalities are seen a full 6 lead and continuous lead two monitoring is recommended to be carried out. ST segment depression or slurring and peaked T waves are hallmarks of myocardial hypoxia and indicate the need for increased supplemental oxygen. Life-threatening arrhythmias such as multifocal or mulitform ventricular tachycardia that is quite rapid (>180) or the beginning of the appearance of an R on T phenomenon indicates increasing oxygen supplementation and treatment with lidocaine. Treatment requires monitoring of blood flow and pressure as well. Blue Tooth Technology by DVM Solutions is very good and I highly recommend its use in routine as well as emergency care.

Wave Form Pulse Oximetry or Plethysmography: These techniques use infrared light and red light (pulse oximetry) or light (plethysmography) emitting diodes and photo-sensors to effectively assess the blood flow and in the case of the oximeter the oxygen saturation of the pulsating arterial

blood. The waveform is diagnostically used to determine low, normal or superanormal blood flow which may indicate hyperdynamic to normal to hypodynamic flow conditions.

Vascular Access – This is accomplished by mini cutdown with an 18 g hypodermic needle used a small knife and the skin over the area of the vein is cut 2-3 cm long and a curved Halstead mosquito hemostat is used to dissect under the vein and then an 18- 14 g IV catheter is inserted and fixed rapidly with tape and staples. Other methods can also be used: feeding tube placement, intraosseous with a IO cannula or an 18 g needle (often the first needle gets occluded with bone and a second 18 g needle is placed).

Since most trauma patients are suffering from a loss of effective circulating blood volume secondary to hemorrhage, fluid therapy forms the cornerstone of resuscitation for the patient in shock. Large bore peripheral or central catheters should be used for vascular access because these patients may require large volumes of fluid in a very short period of time. Fluid therapy consists of the use of both crystalloid (isotonic and hypertonic) solutions and colloid (biologic and synthetic) solutions. (Rudloff) In the patient with uncontrolled hemorrhage, fluid resuscitation may need to be restricted until the hemorrhage has been controlled. If the actively bleeding patient is aggressively resuscitated with fluids hemorrhage may worsen, and systolic BP should not exceed 90 to 100 mm Hg until the hemorrhage is controlled. This is a controversial form of resuscitation called hypotensive resuscitation which will be discussed in more detail in a subsequent article. Attempting to normalize BP before significant hemorrhage is controlled may lead to a worsening of the shock state, a coagulopathy from both loss of clotting factors and dilutional effects of the crystalloids, and increased post-resuscitation complications, especially tissue edema.

Crystalloids. These should be thought of as interstitial rehydrators not intravascular volume expanders. Sodium is the major electrolyte in crystalloid solutions and sodium concentrations in the different body compartments govern the distribution of crystalloid fluids. Within 1 hour approximately 75 to 80 percent of isotonic crystalloids administered will have redistributed to the interstitium or have been eliminated through the kidneys. (Griffe) As a result crystalloid solutions should not be administered slowly if the goal is improvement of intravascular volume. Hypertonic saline (HTS) administered as a 7.5 percent solution at a dose of 4 ml/kg body weight intravenously will cause rapid intravascular volume expansion; however, the effect is short-lived if HTS is not given with colloids because the sodium rapidly redistributes. Hypertonic saline has been reported to have a mild positive inotropic effect and to improve cerebral perfusion pressure by improving rheology. (Ducey, Velasco) Due to the extreme hypertonicity and high sodium concentration, HTS ideally should not be given to hypernatremic or severely dehydrated patients. HTS has also been shown to decrease adhesion molecule expression thus decreasing WBC margination and endothelial injury. Patients with head injury and lung injury have particularly benefited by the use of HTS or HTS mixed with a colloid to provide some sustained effect.

Synthetic colloids such as dextran 70 or hydroxyethyl starch. These are large molecular weight substances that exert a colloid osmotic pressure. As a result they improve intravascular volume which leads to improved blood pressure and perfusion. They also help in the prevention of endothelial, interstitial and intracellular edema. If the patient is actively hemorrhaging the colloids also will be lost from the vascular space. High molecular weight colloids should be used whenever possible to improve the duration of action. Synthetic colloids may contribute to bleeding tendencies which can be a concern with trauma patients. This is more likely to occur with dextrans but may be seen with hetastarch at high doses (greater than 20 ml/kg). Coagulation abnormalities are likely due in part to dilutional effects, but dextrans also interfere with platelet action. (Griffel, Concannon) Although clinical bleeding is not reported to be a major problem with hetastarch, it has been the authors’ clinical experience that the administration of shock volumes of hydroxyethyl starch (20 ml/kg body weight) may be associated with increased capillary bleeding if surgery is required. The oxygen carrying colloid Oxyglobin has also been used as a volume expanding colloid and is recommended particularly when hemoglobin concentrations are low.

Whole blood transfusions may be indicated. It has been suggested that the hemoglobin (Hg) level should be at least 10 g/dl; however, in the healthy individual with an adequate intravascular volume, a Hb of 7 g/dl may be sufficient. (Carrico) In the severely injured patient the Hb levels may need to be higher than anticipated to help maintain an adequate delivery of O2 to the cells. Oxygen delivery (DO2) is calculated as the product of cardiac output (measured with the use of a Swan-Ganz pulmonary artery catheter) and the arterial O2 content. Therefore DO2 can be increased by increasing the Hb or increasing cardiac output. It is evident from the chart that even a Hb of 10 g/dl will be insufficient for delivery of adequate O2 to the cells if cardiac function is depressed. This may occur if the myocardium is contused, arrhythmias are present, or there is depressed cardiac contractility due to sepsis or concomitant systemic infection. Usually blood products are administered over several hours, however in the acutely hemorrhaging patient blood may need to be administered as quickly as the patient is losing it. The actual volumes of blood products required will depend on the amount of blood lost and the clinical status of the patient.

Plasma and Fresh Frozen Plasma. This is recommended in medical emergency patients that have hypo-proteinemia or hypoalbuminemia. This is common in patients with parvovirus enteritis and in other disease processes of the intestine that have a protein loosing component such as bacterial inflammatory bowel disease. Other protein loosing processes such as peritonitis, glomerular nephritis, major burns or wounds are also disease processes that may indicate the need for plasma transfusions. Total solids or plasma protein below 4.0 grams per deciliter or albumin below 2.0 to 2.5 grams per deciliter would be laboratory indicators of the need for plasma. Fresh Frozen Plasma (FFP) which may be available commercially is indicated for patients with low clotting factors that are short lived especially factor seven. This may occur with many entities that are involved with plasma protein losses and causes of disseminated intravascular coagulation. FFP is also indicted in entities where antithrombin 3 is also low. This occurs in such protein loosing entities and burns, peritonitis, enteropathies, and nephropathies.

Autotransfusion. In situations where blood transfusions are not readily available the patient can be autotransfused with blood collected from the thoracic or abdominal cavities. If there is evidence of a ruptured intestinal tract, blood collected from the abdominal cavity should only be used as a last resort. The patient’s blood is collected as aseptically as possible and reinfused. (Crowe) Bubble formation should be avoided during the collection process to decrease lysis of erythrocytes. Blood collected for autotransfusion often does not clot and the need for anticoagulants is uncertain. (Symbas, Broadie) However, it is always safest to use an anticoagulant and give the blood through a 20 micron filter. In emergency situations the time required to mix the blood with an anticoagulant and administer through a small filter (which slows administration rates) may not be available, and the blood should be administered as soon as it is collected. Heparin should not be used as an anticoagulant. Disseminated intravascular coagulation (DIC) may result from autotransfusion due to the infusion of activated products of coagulation and fibrinolysis. (Carrico) Coagulation parameters should be monitored post autotransfusion and, if there is evidence of DIC, treatment should be instituted. Clotting factors should be replaced using fresh whole blood or fresh frozen plasma (FFP) (depending on the need for red blood cells and availability of blood products). Administration of low dose heparin n (50 u/kg body weight SC q8hr) which activates antithrombin, may be useful in the treatment of DIC.

Hypertonic Saline (6- 7.5%) without and with a synthetic colloid. Infusion 5 ml per kg of this per cent of saline will cause a flux of interstitial water into the vascular system rapidly. It also increases vagal activity and causes vasomotor tone enhancement and decreases endothelial adhesion molecule activity. The vascular fluxes are short lived (lasting less than one hour) unless the hypertonic saline solution is infused with a colloid such as hetastarch or dextran. One ml of 23% solution (commercially available) that is mixed with approximately 4 ml of 6% hetastarch provides a solution that is slightly less than 6% hypertonic saline. This mixture is recommended to be used clinically for patients in shock that are not dehydrated or suspected of having an uncontrolled hemorrhage.

Recent research suggests that hypertonic saline with a colloid is even suggested as the resuscitation fluid of choice in the face of dehydration, and in shock associated with head injury or pulmonary injury and in possible uncontrolled hemorrhage (but with less amounts given). The reason is principally based on the finding of less "secondary hit" and edema associated with the shock caused by the activation of inflammation.

Oxyglobin: Oxygen Carrying Colloid (OCC) The latest fluid of choice that has been showing remarkable success as a resuscitation fluid is a polymerized stable hemoglobin containing colloid that uptakes and carries and deposits molecular oxygen similar to red cell bound hemoglobin. Because it is "free" in the plasma it provides an advantage to whole blood in that it flows freely in vessels that have been compromised to red cell flow such as in microvascular blockage caused by clotting, trauma, edema and lower flows. Although further work needs to be accomplished there is no doubt the use of OCC will continue to a vital part of resuscitating any patient that has an increase demand for oxygen and where this demand can not be met by the cardiovascular system. Conditions were OCC has been shown to be beneficial include ALL forms of shock, sepsis, trauma and swelling, anemia, and in cases where there is vascular compromise locally or globally. Even doses as low as 3 ml per Kg body weight have been shown benefit. The product does not have a very long half life and is gone from the blood stream within 20 to 40 hours. I personally have seen patients with bad shock and resuscitated with OCC early and even somewhat late and they did not get the typical gastrointestinal hemorrhage commonly seen in dogs post resuscitation.

Human Albumin (5 and 25%) is very good to increase colloid osmotic pressure. 25% concentration pulls water into the circulation (3.5 ml per 1 gram given) therefore this must be taken into account when administering. In significant shock states it is recommend to dilute 25% 1: 4 with a crystalloid. In hypoproteinemic states it can be given slowly with the total daily dose not to exceed 2 g/kg. In severe peritonitis cases with hypotension I have given 1 50 ml bottle every1/2 hour to a 25 kg patient ALONG WITH HETASTARCH 1:3 with very good results.

The volume and rate of fluid administration will depend on the patient’s hemodynamic parameters. In general, hemodynamic parameters should be returned to normal as fast as possible. If the patient is tachycardic and assessed to be hypovolemic, fluids should be given until the heart rate returns to close to normal (generally about 110-140 beats per minute). If the BP is low or not detectable, fluids should be administered as fast as possible to return BP to normal as soon as possible. There is a great deal of controversy surrounding the type of fluids to use. If the patient is in shock because of hemorrhage large volumes of crystalloids should be avoided since interstitial edema may result. Guidelines are offered below. If the patient is hypotensive or normotensive and tachycardic, a bolus of a crystalloid of 30 ml/kg is followed by reevaluation of the patient’s heart rate and BP. If the hemodynamic parameters improve and then deteriorate, or if they have not improved, a synthetic colloid is administered in slow intravenous boluses of 5 ml/kg up to 20 ml/kg and the crystalloid administration rate is decreased to 30 ml/kg/hr. If the patient stabilizes after the bolus of crystalloid then the crystalloids are continued at maintenance rates. If the patient has no detectable BP or if the BP is below 50 mm Hg systolic, synthetic colloids (20 ml/kg), or hypertonic saline (4 ml/kg) and a synthetic colloid (20 ml/kg) should be administered. If blood is available it can be substituted for the synthetic colloid. If the patient is thought to have a possible uncontrolled hemorrhage then all fluid administration is guided by the patient's blood pressure and hypotension is maintained slightly (until the bleeding is believed to be under control).

The packed cell volume and total plasma protein should be reevaluated after the first 30 to 60 minutes in any patient who is not responding to fluid resuscitation or any patient which has received more than 50 percent of its blood volume in fluids. If the packed cell volume is less than 20 percent or has dropped by more than 50 percent red blood cells are recommended. Since these patients also will be predisposed to a dilutional coagulopathy FFP should be concurrently administered. If fresh whole blood is available it is the blood product of choice in trauma patients. If the patient appears to be adequately volume resuscitated based on CVP and BP is still lower than the target value a positive inotrope (dobutamine hydrochloride c 5-20 mcg/kg/min in the dog, 2-5 mcg/kg/min in the cat) should be considered. Positive inotropes should be given only if the patient is euvolemic. If the blood pressure does not respond, vasopressors may be indicated (dopamine ). Since vasopressors cause vasoconstriction which can decrease tissue perfusion and thus tissue oxygen delivery, they should be avoided unless absolutely necessary. The authors do not recommend giving vasopressors unless the BP remains below 80 mm Hg with fluid resuscitation and positive inotropes.

Every major trauma patient should be immobilized to a board and trauma films taken to assess spinal and pelvic injury, diaphragm, thorax and abdomen. Tapping a patient to a clear plexiglass board is recommended using duct tape as it does not show up on radiographs. Lateral radiographs should include the skull to the tail and time taken to review them carefully. The taping also eliminates the patient from being able to move much which often decreases his pain and helps prevent clots from moving away from injured and bleeding tissues. If the patient is having difficulty with breathing this step is modified to position the patient in a position of comfort rather than lateral…breathing before circulation, circulation before spine concerns.

Electrocardiogram A lead II electrocardiogram should be assessed for the presence of any arrhythmias since hypoxia and cardiac trauma frequently lead to ventricular premature contractions (VPC). Ventricular premature contractions should be treated if the patient is tachycardic, if the arrhythmia is interfering with perfusion (significant pulse deficits), if there are multifocal VPC’s, or if there is R-on-T phenomenon. Lidocaine or procainamide may be used. DMV Solutions (210-373-9627) Greg Piel has atraumatic alligator clips I love!!

All patients should be assessed with common sense and history and physical examination as the cornerstone of assessment and decision making. However there are other tools that can help in the emergency assessment. These include pulse oximetry, toe web -temperature, venous blood gases, whole blood lactate, urinary output, end-tidal CO2 , thoracic and trauma radiographs, quick-look ultrasound of the thorax and abdomen, and diagnostic peritoneal lavage; as well as common lab Analyses such as PCV, TS, glucose, electrolytes, ALT, ALK PHOS, amylase, BUN, creatinine, urinalysis.

Basic laboratory tests such as hematocrit, total plasma protein, glucose, and blood urea nitrogen should be performed on every patient. These tests require minimal blood and usually can be run off the volume in the hub of the catheter stylet. If there is a concern that the patient is actively hemorrhaging internally the PCV should be monitored as frequently as every 15 to 30 minutes until it stabilizes. If there is no obvious evidence of active hemorrhage the PCV should be check in 2 to 4 hours.

Whenever possible laboratory tests including venous blood gases, electrolytes, serum chemistries, a complete blood count including platelet count with evaluation of a blood smear, and coagulation indices should be evaluated in seriously injured patients. Blood glucose and electrolyte levels should be kept in a normal range. Albumin should be kept greater than 2.0 g/dl. Venous blood gases can be used to evaluate metabolic and respiratory acidosis in the trauma patient. It is important to correct metabolic and respiratory causes of acidosis since a low pH can compromise myocardial performance, cause vasodilation, and interfere with the function of vital cellular enzyme systems. A high PaCO2 level (greater than 50 mm Hg) is consistent with ventilatory insufficiency. Ventilation should be reassessed and treated as discussed above.

Metabolic acidosis usually is a lactic acidosis associated with poor peripheral perfusion. Since this should be correctable with fluid therapy in almost all cases bicarbonate therapy rarely is indicated. There are no absolute guidelines for administration of bicarbonate in the treatment of metabolic acidosis in trauma patients. If the venous pH is less than 7.0 and the bicarbonate level is less than 12 mEq/L after initial fluid resuscitation, cautious bicarbonate therapy should be considered. BASE DEFICET OF 6 or GREATER = COMPROMIZED STATE THAT DEMANDS AGGRESSIVE ATTENTION. COULD ALSO MENTION WHOLE BLOOD LACTATES WITH HANDHELD UNIT (ACCUSPORT) . TRENDS ARE THE KEY

An activated clotting time (ACT) and a platelet estimate from a blood smear provide an early rapid assessment of coagulation indices. If the ACT is prolonged (greater than 120 seconds in a dog and 90 seconds in a cat) serious consideration should be given to administering FFP. It is the authors’ clinical impression that the ACT may prolong to 180 seconds in dogs with the use of hetastarch. If the ACT is prolonged beyond 180 seconds the authors recommend giving FFP. If the platelet numbers decrease by 50 percent or more after fluid resuscitation the authors recommend that an ACT and platelet estimate should be repeated in 4 to 8 hours. IT IS ALSO THE AUTHORS’ IMPRESSION THAT ACT IS FREQUENTLY PROLONGED IN THE SEVERELY BLUNTLY INJURED PATIENT as they have a traumatic inducted consumptive coagulopathy. It is important to consider FFP for AT3 and low dose heparin in cases with significant injury but in which no active bleeding as occurred for many hours post injury. This is to help prevent DVT, PE and other microembolic driven phenomena post injury

One of the hallmarks of good patient care in emergency medicine is repeated assessments. Assessment of the patient's airway, breathing, and circulation should be done at least hourly following admission. A common protocol involves repeated ABC assessment and vital sign monitoring and recording of the findings in a progress note and flow chart format respectively.

Flow charts have the time listed at the top and the indices being monitored on the vertical axis such as follows: 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900

Respiratory rate……. Breathing effort (1-4). Heart rate in bpm……

Pulse strength (1-4)… Capillary refill time…Mucus membrane color…. DOPPLER flow sound strength

Temperature…………CVP…………………(or Jugular Vein Distension Amount and Time) Blood pressure………

Then rates and values are identified in which "alarm bells" should go off. These values when recorded by paraprofessionals caring for and assessing the patient will alert them that the veterinarian should be alerted. If the veterinarian is doing the monitoring and these "alarm values" are reached and recorded they will serve as signs that something is wrong and further assessment or treatment is indicated. An example is HR. If it decreases below 45 or rises above 160 or changes more than 25% then an "alert" should be made or announced to the veterinarian indicating that something is possible wrong.

Abdomen The abdomen should be carefully auscultated for bowel sounds, and percussed for areas of dullness that would suggest fluid in the abdomen. The abdomen should be palpated thoroughly but gently because organs such as the liver or spleen may be injured and additional pressure could cause them to bleed excessively. The caudal abdomen should be carefully palpated for the presence of a urinary bladder. A rectal examination should be performed and the presence of blood, pelvic fractures and pulse strength of the internal iliac arteries should be noted.

Ultrasonography: This is a very useful diagnostic tool in the emergency room for determining the presence of free intraabdominal fluid, as well as solid viscus injury. (rozycki95) 7 It can be useful also in the diagnosis of a diaphragmatic hernia and pericardial effusion. If there is evidence of cardiac injury, or the patient’s cardiovascular parameters do not improve in response to resuscitation, an echocardiogram ideally should be performed. Blunt trauma patients may have decreased cardiac contractility, or lack of synchronous and even muscular wall contraction . a positive inotrope (dobutamine hydrochloride c 5-20 mcg/kg/min in the dog, 2-5 mcg/kg/min in the cat) may be indicated if there is evidence of severe cardiac muscle dysfunction on ultrasound examination.

Abdominocentesis and Diagnostic Peritoneal Lavage: Four quadrant abdominocentesis should be performed if there is any concern for intraabdominal injury; however, there can be a high incidence of false negative results with abdominocentesis. Diagnostic peritoneal lavage (DPL) should be performed in the face of a negative abdominocentesis when there is concern for intraabdominal injury that may require emergency surgical treatment (severe hemoabdomen, uroabdomen, rupture of the gastrointestinal tract). The technique of DPL is also recommended in all acute abdomen cases where surgery is contemplated as possibly being necessary not confirmed with radiographs or ultrasound revealing free air or bowel obstruction, etc.

DPL TECHNIQUE : The patient is placed in left lateral recumbency so that the spleen falls away from the midline. The urinary bladder should be emptied. A surgical prep is done of the ventral abdomen just caudal to the umbilicus. A local anesthetic block is placed and a stab incision made with a number 11 scalpel blade. A commercial DPL catheter or a multi-holed catheter is inserted on the ventral midline or just lateral to midline two cm caudal to the umbilicus. The catheter is inserted in a caudal direction. Warmed balanced crystalloids (lactated Ringer’s solution, saline) are infused into the abdomen . A volume of 20 ml/kg is infused typically; however, fluid in the abdomen will compromise diaphragm excursion, and if the patient’s ventilation is being compromised fluid infusion should be discontinued. Once the fluid is infused the patient’s abdomen is gently massaged to help move the fluid around and a sample of the lavage fluid is obtained. This can be evaluated for packed cell volume (PCV), total solids, white blood cell count, chemistries and cytology. A PCV greater than 15 to 20 percent indicates a significant hemoabdomen. The catheter should be left in place and the fluid resampled in 5 to 10 minutes. If the PCV increases by 5 percent the patient has severe ongoing hemorrhage and an exploratory celiotomy is indicated. A potassium, creatinine, or urea nitrogen greater than serum level is consistent with a ruptured urinary bladder. Presence of plant fibers indicates a ruptured bowel. A gram stain should be performed if bacteria are seen in order to determine the class of antibiotic to administer. If DPL is done prior to 3 hours post injury false negatives have occurred as it takes that long to detect ruptured bowel or hollow viscus. If so KEEP THE CATHETER IN PLACE AND REPEAT THE LAVAGE AT APPROPRIATE TIME. IF UNSURE OF RESULTS ALSO LEAVE THE LAVAGE CATH IN AND DP REPEATED LAVAGES… VERY ACCURATE IN DETECTING A DYING PORTION OF BOWEL OR OTHER SEPTIC FOCUS.

Cranial nerves should be assessed and a fundoscopic exam should be performed. The ear canals should be evaluated with an otoscope for the presence of fluid (blood, cerebrospinal fluid).

The entire body should be palpated gently for fractures, swelling, and wounds. The limbs of the patient should be palpated; however, fractures may worsen with movement and if the animal is recumbent only spinal reflexes and the presence of limb sensation should be assessed until radiographs have been taken. This is especially important if the patient might have a fractured spine. Fractures of the distal limbs (below the elbow and stifle) should be stabilized following assessment of the injury. Newspaper splints or splints made from bubble wrap are placed easily and rapidly and are very effective as temporary splints. Radiographs can be taken through these materials. Spica splints made of newspaper are very useful for the temporary immobilization of fractures and dislocations of the scapula, SH joint, humerus, HR joint, and proximal radius/ulna of the front leg and of the femur, FT joint, and proximal tibia of the rear limb. The spica extends from the spine to the distal end of the toes of the respected limbs. They are placed with mild compression to provide the immobilization needed. Therefore the limbs sensation and circulation are assessed before and after placement to assure no or minimal compromise.

Any areas that appear swollen or bruised should be clipped to check for possible wounds. All wounds should be clipped in order to be able to assess properly the extent of the injury. Use exam gloves. During the preliminary resuscitation it may not be appropriate to take the time to clip the wounds, in which case they should be covered with sterile saline or a sterile water-soluble lubricant to minimize desiccation. Sterile dressings should be used whenever possible since most wounds are contaminated but not infected at the time the animal presents, and protecting the wounds helps avoid infection. Broad-spectrum antibiotics should be administered intravenously if wounds are evident if at all possible. A STERILE TOWEL SHOULD BE USE TO WRAP THE AREA INVOLVED. IT SHOULD BE DONE IF AT ALL POSSIBLE TO MINIMIZE CONTAMINATION WITH THE HOSPITAL ENVIRONMENT AND APPLIED ON ADMISSION.

If 24 hour observation and care is able to be provided this makes provides options many veterinarians do not have. If it is not available then it is recommended to error in the direction of being more aggressive rather than being more conservative. As an example; if a dogs is having a slight increase in ventilatory rate caused by a diaphragmatic hernia it is far better to operate early rather then to wait. The dog could decompensate in the middle of the night and be dead in the morning when the first technicians arrive for the day. Sad but real …there is no such thing as a stable compromised pet that has been seriously injured; there are no such thing as a stable acute diaphragmatic hernia patient. Surgical texts were written by people who have not had the experience on the front-lines in my opinion. Common sense should provide an insight as to what is best for the pet, sitting in a cage with an ever increasing "work of breathing". These cases need to be operated as soon as possible, preferably in the next 1-2 hours not the next morning when effort is even more labored and respiratory failure is now eminent.

Hallmarks of severe intraabdominal hemorrhage that will require surgery if the patient is to survive include the "stand out" signs of severe shock, expanding hemoabdomen, and often the look of anxiousness and "impending doom" on the patient. This includes the canine and feline patient as well as the human patient. Without surgery mortality rates range from 70-100% depending on the center and the team, amount of blood available, cause for the severe hemorrhage, and the owners financial support. Properly selected patients may be treated conservatively with multiple blood transfusions without surgery if they stabilize and remain that way; and pass the rest of the criteria indicating they can remain unoperated. These criteria include a negative DPL (diagnostic peritoneal lavage) for a septic focus, negative chest and abdominal films indicating the need for surgery, e g., no evidence of a diaphragmatic hernia and no free gas, maintained benign clinical signs on repeated exams, and negative findings on other tests (ultrasound, cystourethrogram).

A patient that remains unstable or becomes unstable following supportive care is explored at our institution if the finances are in place to allow it. If not the patient is continued with supportive fluids (colloids, blood or Oxyglobin) 24-72 hours of intravenous antibiotics, sedation and analgesia and small doses of acepromazine titrated to keep the patient quiet with arterial blood pressures kept between 65 and 80 mmHg systolic (called hypotensive resuscitation). Immobilization and limited counterpressure is provided with towels wrapped around the abdomen and pelvic limbs and secured with duct-tape. Duct-tape is also used to kept patients immobilized for 12 to 18 hours on a board. This type of management is used for those in which surgery is also planned but time is required to get the operative team together. Limited counterpressure, hypotensive resuscitation and immobilization have been used effectively in a published series of both dogs and humans suffering from acute abdominal hemorrhage.

Operative techniques most often required for those being operated include thorough exploration, compression of bleeding sites, temporary occlusion blood supply involved with the bleeding site, removal of an organ or part of an organ that is still bleeding or has become necrotic or is involved with pathology that is the cause of the hemorrhage, ligation of torn vessels, reassessment following irrigation to ensure hemostasis is continuing, and closure (except in septic peritonitis).

Diagnosis of hemoabdomen is definitively performed primarily through the use of centesis with a multi-holed catheter and + or - the addition of 22 ml/kg of warmed sterile physiologic salt solution, i.e., diagnostic peritoneal lavage (DPL). Prior to DPL chest and abdominal radiographs should be obtained. Following multi-holed catheter placement blood is usually easily aspirated from the abdominal cavity in cases of severe acute peritoneal hemorrhage however this does not indicate whether the hemorrhage is continuing and is NOT an absolute indication that surgery must be performed. Continuing intraabdominal hemorrhage can be determined by performing another sampling of the lavage fluid 10-15 minutes later unless clinical signs are so unstable that surgery is already being prepared for; The abdomen is then massaged and sampling the fluid done again. If the lavage fluid PCV is increasing then ongoing hemorrhage is diagnosed. In cases that are positive with lavage that are very unstable or remain unstable following volume replacement therapy, continued hemorrhage should be assumed and no further abdominal diagnostics are indicated and surgery is indicated.

Use of abdominal ultrasound (US) is practical in diagnosing acute hemoabdomen and in helping to determine whether surgery is indicated. The probe is used to guide the examiner's hypodermic needle into a pocket of free abdominal fluid. Repeated examinations can help determine whether more free-fluid (blood) is accumulating. US can provide information of the possible source of the hemorrhage and is particularly effective in assessing splenic and hepatic pathology.

The ultimate diagnostic "assessment tool" for the hemoabdomen patient is exploration of the abdominal cavity through wide exposure created on the ventral midline from xyphoid to pubis. It is recommended if signs of acute abdomen persist (vomiting, pain, shock-despite ongoing volume support, continuing abdominal expansion) or any the lab, radiographic, or ancillary tests are directive. Complications of a negative celiotomy are very few and the complications of a missed surgical abdomen can be catastrophic. Therefore, when in doubt, exploration is always recommended.

Because of financial considerations and lack of backup support and training in the surgical management of severe hemorrhage in veterinary medicine, many more patients are treated conservatively than surgically. However there are cases where the animal will die without surgical intervention. Support personnel are critical to the successful management of the patient as these patients require one person to monitor anesthesia, provide controlled volume support, pressure support, positive pressure ventilation and because of the critical nature of the injuries a surgical assistant is mandatory. Therefore a contraindication for performing surgery on the hemoabdomen case is NO HELP. Before a team is together measures should be taken to slow the hemorrhage down of stop it using a combination of limited counterpressure on the abdomen and pelvic limbs and sedation/analgesia to keep the patient from moving or becoming relative hypertensive (systolic > 100 mg).

The "Entrance" Criteria required for successful surgery that ideally should be in place prior to beginning the incision are the following: intubation with a cuffed ET tube and the patient on a combination of opioids, very small amounts of sedation/tranquilizer, small amounts of a hypnotic drug such as halothane or isoflurane; ventilation as needed (best done with a bellows in box type mechanical ventilator such as a Hallowell); and monitoring with wave form ETCO2, SaO2, Doppler blood flow and blood pressure, ECG, esophageal stethoscope, core temperature; two large bore catheters in the peripheral veins; ongoing fluid support, as needed whole blood or packed RBC’s and fresh frozen plasma, a means of active warming of the patient while in the OR to help prevent hypothermia (water or air circulating heating pad , Bair Huggar, Augustine Med Inc., Eden Prairie, MN), oxygen carrying colloid (Oxyglobin), and appropriate instrumentation such as Balfour Retractor, Pool suction type, Yankauer suction tip, Mixter right angle forceps, DeBakey thumb forceps, liga-clips, silk for ligatures, surgical headlight, and OR electrocautery unit.

It also immobilizes the animal and internal organs to some degree. Has worked 80+ % of time to prevent need for Sx.

There are three key methods of treatment for catastrophic hemorrhage and the shock syndrome which accompanies it:

1. Application of counterpressure to the abdomen and caudally; which slows or stops hemorrhage caudal to the diaphragm, autotransfuses blood centrally, and increases arterial pressure via its effect in increasing systemic vascular resistance. The counterpressure can be used as a stop gap measure that can be used to slow down the bleeding, allowing time to gather the surgical team together. It can also be used as the definitive means for hemorrhage control when funds are limited or coagulation times are prolonged as what might occur with rodenticide toxicity or severe DIC associated with significant blunt trauma and profound hypothermia.

2. Rapid blood volume restitution with blood, plasma, colloid plasma expanders, hypertonic saline, and balanced salt solutions, until blood pressure is slightly above normal.

3. Rapid thoracic, abdominal, or limb entry and indirect internal control of the hemorrhage by occluding the arterial supply leading to the site of the hemorrhage; often requiring the use of vascular "loops" or temporary wide vascular tourniquets.

4. Identification of the bleeding vessels and their ligation or rarely their repair.

We will discus each on of these key treatment modalities subsequently. All of these modalities, must be performed quickly in the patient presented. Because of impending vascular collapse in the vast majority of cases of severe hemorrhage, due to a shear loss of blood volume in a short period of time, very rapid volume restitution and the control of the hemorrhage are keys to survival. But these do take time to implement. To buy this time necessary the use of counterpressure is very important.

Counterpressure can be implemented very quickly while tests are being started to correctly diagnose where the hemorrhage is occurring. If the catastrophic hemorrhage is occurring in the thoracic cavity counterpressure will not be as effective, as this will not stop or slow down the hemorrhage. In fact it may cause more bleeding to occur. Therefore, if catastrophic hemorrhage is diagnosed by thoracentesis or highly suspected from the evidence present, e.g., a gunshot wound in the chest in an animal in severe shock, a resuscitative thoracotomy should be performed and the bleeding structures temporarily occluded.

Resuscitative thoracotomy and cross clamping of the descending aorta may also prove lifesaving or at least a key stop gap measure, in patients that are presented with signs of severe catastrophic hemorrhage from the abdomen and have signs of impending death, e.g., very poor blood pressured, unconsciousness, shallow breathing, very fast or very slow heart rate, and a history of blunt or penetrating trauma.

Resuscitative Thoracotomy: There are other indications for resuscitative thoracotomy other than suspected catastrophic hemorrhage of the chest and possibly the abdomen. These include: 1) admission of a rapidly progressive tension pneumothorax in an unconscious patient; 2) cardiac arrest in a patient that had just been traumatized; 3) cardiac arrest in which external massage and drug support had been performed and to the heart is resistant to therapy;

To begin, following tracheal intubation and beginning of positive pressure ventilation, a quick is exam is performed (primary survey) is completed. If from the exam, either thoracic or abdominal hemorrhage is suspected, i.e., no major bleeding outside these areas is identified and the patient appears to be salvageable, e.g., does not appear to have severe brain or spinal cord injury, then the resuscitative thoracotomy is indicated.

The technique is easily performed using a knife blade to make an incision at approximately the fifth intercostal space on the left (unless otherwise indicated, e.g., gunshot wound on the right). A curved Mayo scissors is then used to puncture controllably into the pleural space at the costochondral junction. The blades of the scissors are opened to allow air in and partially collapse the left lung. Then with the blades partially opened a pushing motion is used to separate all layers of the thoracic musculature.

The opening in the thorax is then opened wider using fingers to stretch the tissues and the Mayo scissors for further push dissection. A Balfour retractor is then inserted quickly and the ribs are spread. The author has found the Balfour retractor to work better and faster than a human rib spreader and retractor (Finochetto, etc.,) in the dog and cat.

Aortic Occlusion (Cross Clamping): With severe hypotension, exsanguinating hemorrhage into the chest of abdomen, and cardiac arrest the descending aorta is then observed and cross clamped using a vascular clamp, Forrester sponge forceps, or rubber shod or gauze wrapped Allis (fascial) forceps. With the latter forceps, their tips are brought together on the opposite side of the aorta. If no forceps is available a loop of umbilical tape or a feeding tube (the preferred method of cross clamping by the author) can be brought around the aorta and tightened (using a hemostat to grip the ends close to the aorta, thus trapping and occluding it atraumatically). Aortic cross clamping directs blood flow centrally, increasing blood flow to the brain and heart significantly while decreasing hemorrhage distal to the clamped area. The technique has also been recommended in human patients suffering from exsanguinating arrest or near arrest as well as patients with very large or rapidly distending abdomens (indicating severe abdominal hemorrhage).

Descending thoracic aorta occlusion significantly decreases the size of the vascular space "requiring" perfusion, increases systemic vascular resistance, and temporarily controls abdominal arterial hemorrhage. The aorta may remain occluded reportedly up to 10 minutes without causing serious complications, (renal, spinal cord, intestine). The maneuver significantly increases blood flow to the lungs, brain, and heart itself. When the occlusion is no longer needed, if its been in place over 5 minutes, it requires gradual removal and concomitant volume infusion because of the secondary vasodilation occurring in the tissues distal to the occlusion. If aortic occlusion is required longer than 5 to 10 minutes (maximum) it is recommended to loosen the clamp or vascular occlusive tube or tape at the end of this period and allow perfusion to occur for a minute and then re-occlude. This helps prevent renal function compromise or paraplegia: the two main complications associated with aortic occlusion.

If upon opening the chest a considerable amount of hemorrhage is present in the pleural space, the patient's body can be turned quickly to drain the pooled blood out or the blood can be aspirated or pulled out into absorbent laparotomy pads, sponges, towels, or cloth diapers. If it is not obvious where the hemorrhage is originating from then more absorbent material is used to pack the chest. These packs are then removed one by one as each quadrant is examined. As the source of bleeding is found direct pressure is applied and clamping and suturing is used as is required to definitively control the hemorrhage. Other sources of hemorrhage are looked for and handled in a similar fashion.

Following arrest of the hemorrhage, complete exploration, definitive repairs necessary, and extensive saline or LRS irrigation (several 100ml in cats and several liters in large breed dogs) the chest is routinely closed after the placement of a chest tube. The hair on the lateral chest in most cases is not clipped either before entry or before taking the patient back to the OR for closure. Long hair is simply parted. No other prep is completed. If the patient begins to become arousal before necessary repairs and closure is completed analgesia is provided by the use of small incremental doses of intravenous narcotic - benzodiazapine combinations, and movement is controlled with the use of small intravenous doses of muscle blockers. The author has found the use of oxymorphone(0.025-0.05mg/kg) - diazepam (0.05-0.1mg/kg) and atricurium(0.25mg/kg) or pancuronium(0.04mg/kg) with very good success. The use of 2% lidocaine or 0.5% bupivicaine for intercostal nerve blocks and on the surface of the parietal pleura in the area of the thoracotomy also has seemed to help in anesthesia control and analgesia during the intrathoracic repair, closure and recovery period.

Surprisingly the infection rate with emergent thoracotomies has been low in the author's experience. With the use of careful cleaning, copious irrigation, and perioperative antibiotics (cephalothin or other first generation cephalosporin at 40mg/kg IV every 6 hours for 24 hours) only 2 out of 20 surviving patients develop a wound infection. None developed a pyothorax. This experience also correlates with similar results reported with the emergent thoracotomy in humans.

External Counterpressure: If a quick exam of the chest and a rapid chest tap are negative (indicating no severe chest trauma or hemorrhage) external counterpressure applied to the pelvic limbs and caudal abdomen can be very effective in temporarily raising systemic blood pressure (both arterial and central venous). This occurs with blood flow preferentially going to the central circulation and brain as well. The use of counterpressure can also be effective in slowing or stopping hemorrhage to or into structures under its influence, even those involving major vessels, e.g., abdominal aorta, vena cava.

The counterpressure works because it exerts external force on vessels under its influence, causing them to become smaller in diameter (radius). Flow through the vessels thereby also becomes smaller in amount, but significantly more so because of the physiologic law of Q (flow) = P (pressure) x R (radius of the vessel) to the FOURTH POWER / L (length). Flow is thus diverted significantly away from the vessels under the influence of the counterpressure. Systemic vascular resistance significantly increases and arterial pressure to the areas of the body not under the influence of the counterpressure rises proportionally.

Because central venous pressure also rises temporarily, peripheral veins are also easier to find and catheterize. This is important in securing a large bore venous catheter for rapid blood vascular replenishment. Central vascular replenishment also is enhanced by the use of the counterpressure because blood previously in the capacitance veins and venules, under the influence of the counterpressure, moves out and into the central circulation. Although this form of "autotransfusion" is said not to be as important as the influence of the increased peripheral vascular resistance by some investigators, it is the author's opinion, based on preliminary research investigations in which dogs were subjected to severe hemorrhage that this venous "autotransfusion" becomes more important in patients with vasomotor tone loss, which occurs in deep shock .

Another means of vascular replenishment that may be possibly occurring with the use of external counterpressure is enhancement of the movement of interstitial fluid into the vascular system via its influence on increasing perivascular tissue pressure.

The counterpressure is applied using a specially designed, commercially available, small animal "antishock" pneumatic garment or by wrapping elastic roller bandage on the pelvic limbs (starting at the toes), pelvis, and caudal abdomen. It is important that pressures applied to the abdomen are significantly limited as compared what was used in the past. Pressure should be limited to only a few mmHg. With the former, the patient is simply wrapped in a garment that contains one to several rubber balloons or bladders. The wrap includes all of the pelvic limbs, pelvis and caudal abdomen, to just caudal to the rib cage. After it is secured the bladders are inflated, starting with the most caudal or distal one until the garment is visibly tightly distended. The next most caudal bladder is then inflated and so on until the patient's blood pressure becomes normal or all bladders are inflated. In catastrophic hemorrhage it has been the author's experience that all the bladders require inflation. Care is taken as the abdominal bladders or segment of the garment are inflated that ventilation is supported by positive pressure breathing (most often required in all deep shock patients anyway but the abdominal counterpressure reduces compliance and consequently tidal volume in spontaneously ventilating cases. It is also particularly important in patients with a diaphragmatic hernia or pneumothorax which by themselves causes respiratory compromise. When external counterpressure is added this often causes further compromise which can be fatal if ventilatory support is not aggressively provided.

With the use of wide elastic rolls of bandage placed on in a circular "barber pole" fashion it is important not to wrap so tight that severe respiratory compromise occurs. Placing 1/2 to 1 pound of cotton on the ventral abdomen before starting to apply the wide elastic rolls on the abdomen can also help provide more pressure to the splanchnic viscera, thus increasing systemic vascular resistance more and raising arterial blood pressure even more. If intraabdominal hemorrhage is suspected the use of the cotton roll is also beneficial in raising abdominal pressure even more, thus helping slow down intraabdominal hemorrhage.

The amount of pressure that should be placed on bleeding luminal structures to significantly slow down hemorrhage is not as great as one might think. Only 2 lbs per square inch is enough pressure to stop or drastically reduce blood flow to tissues under the bandage. Correct application allows one to place a finger between the bandage and the skin. This also corresponds to the pressure required to immobilize fracture segments enough to prevent further soft tissue injury as well. Therefore counterpressure may also be applicable in helping support and temporarily stabilize pelvic and femoral fractures, particularly those in patients with coagulation disorders or persistent signs of shock (indicating possible continued hemorrhage).

The use of counterpressure by the author has been successful also in helping slow or stop hemorrhage that may be occurring underneath the garment or bandage. This has been proven in several research experiments involving pigs or dogs in which bleeding from the caudal abdominal vena cava, aorta or renal artery and vein was induced. As vessel diameter becomes smaller, due to the influence of the counterpressure, again the flow through the bleeding vessel reduces by a power of four. This then corresponds to a reduction in bleeding rate also by a power of four.

Clinically use of the counterpressure for internal hemorrhage control has provided extra time to prepare for surgery, which in itself, can be a major but necessary undertaking.

In many cases the bleeding produced experimentally was able to be completely controlled and stopped with the use of the counterpressure. This therefore provides another treatment option for owners to pets. If exploratory surgery is not affordable the counterpressure may remain for several hours, hopefully leaving it in place until after a large internal clot has formed and effectively stabilized the bleeding vessel. Effectiveness has been documented in this regard.

In a series of 30 cases of severe hemorrhagic shock, studied by the author, 20 responded by noting increased levels of awareness, some actually becoming fully conscious after being completely unconscious on admission. Blood pressure increased in all cases in which heart rate was not profoundly decreased or absent. In several patients, no palpable pulse was present on admission. Following the application of the garment and its inflation a palpable pulse was present. Similar results have been reported following the use of the garment in human patients suffering from catastrophic hypovolemic shock. The results have been so profound in the resuscitation of the trauma patients that one author on the subject stated recently "the development of this (external counterpressure) is as important to the circulatory support of the trauma patient as mouth-to-mouth breathing has to the cardiopulmonary arrest patient".

The counterpressure device, once in place and applying pressure to the abdomen, should remain there until vascular volume has been restored. If cases continue to have unstable vital signs and other signs of deepening shock, after volume is restored, this indicates continued hemorrhage that will require surgical intervention. In these patients the counterpressure is continued until just before the surgery is to begin. Removal in these cases should be done quickly, the abdomen prepped very rapidly while a hand is held over the internal hemorrhaging area, and rapid surgical approach to the area preformed.

In all other cases (fortunately the majority) the vital signs stabilize with the use of the counterpressure initially and the infusion of balanced salt solution. Following the restitution of all vital signs, including measured blood pressure or estimated pulse strength back into the normal range or slightly higher, the counterpressure device can be slowly removed while monitoring blood pressure and heart rate. With pneumatic devices a small amount of air is released every few minutes, provided the patient's pressure does not fall more than 5 mmHg. until all of it is evacuated.

If a compressive circumferential dressing was used it is gradually removed cutting or loosening it, starting at its cranial most border. Again if blood pressure drops more than 5 mmHg then removal of the garment should be stopped and more volume replacement be instituted until pressure is back up to baseline.

Removing counterpressure devices rapidly, particularly following shock associated with serious injuries, can result in catastrophic hypotension secondary to the significant decrease in systemic vascular resistance that occurs.

Rapid Volume Resuscitation: Once the counterpressure is applied, which should only take a few minutes, attention should be made toward restoring circulating blood volume as rapidly as possible. Indications of the restoration of more than adequate blood volumes are blood pressure normalization to slightly higher, slightly higher mean central venous pressure, return of mucous membrane color and normal capillary refill time, return of consciousness and responsiveness. As a rule of thumb, resuscitative volume replacement should be rapidly enough to restore systemic arterial blood pressure and central venous pressure to slightly above normal within 15 minutes (maximum)(17,42).

Peripheral IV Catheters - Most patients vascular access is obtained by getting in at least one cephalic vein, large bore catheter (14 gauge in medium to large dogs, down to 18 to 20 gauge in cats and very small dogs). Two cephalic vein catheters are preferred if peripheral vascular access is obtained so infused fluids and blood are introduced cranial to the diaphragm.

Central IV Catheters - Even more acceptable in those patients with extreme hypotension secondary to blood loss is to obtain central venous access with a very large bore catheter or feeding tube. A feeding tube is preferred over stiffer polyethylene catheters. A large bore feeding tube (12 French in very large dogs to 6 French in cats and small dogs) can be placed into the Maxillary vein via a quick cut down procedure. The jugular vein is also readily available and easily cannulated in most patients.

Placing a catheter in the maxillary or jugular vein and advancing the tip into the cranial vena cava allows for central venous administration and intermittent pressure monitoring. This size catheter allows rapid assessment of central venous pressure by simply lowering the fluid bag and noting when the fluid in the drip chamber of the administration set stop dripping. This is helpful in determining the amount of fluid and/or blood replacement required. It should be very rapidly administered until CVP is slightly above normal.

Intraosseous Administration - Resuscitative volume replacement can also be administered through one or two large bore intraosseous needles placed within the medullary canal of either the humerus, femur, or possibly the tibia via cannulas (bone marrow biopsy needles or spinal needles) placed in the greater tubercle, trochanteric fossa, and tibial plateau respectively.

Most drugs and biological products that can be administered intravenously can be administered intraosseously as well with very rapid uptake. In one report the uptake was actually better via the IO via femur route over the IV (cephalic vein) route.

It has been the author's experience that IO volume rates are generally limited to slightly less than what can be obtained with a similar sized catheter placed IV, Smaller volume rates have been administered through the iliac crest with out complications. In very small patients the IO route, because of ease of cannula placement, is often preferred over the IV route, as it is usually very difficult to establish an IV catheter in these animals, especially when in shock.

Generally a polyionic balanced electrolyte solution such as lactated Ringer's solution is the initial fluid infused, chiefly because of a financial consideration and generally it works OK. It might require at least 1 blood volume; giving up to 90ml/kg in dogs, and 55ml/kg in cats. There is now current thinking that volume should be limited to only that required to keep kidneys perfusion well. This required a blood pressure of 60 mmHg systolic. This is measured by Doppler and had been found to be a very accurate way of estimating pressures.

In patients where severe blood loss is obvious, rapid restoration of lost blood is ideally replaced with whole blood transfusions, autotransfusion of pooled thoracic or abdominal blood, or plasma / synthetic colloid and packed red cell administration.

Contrary to what is written in some emergency texts, this author firmly believes and condones the use of rapid, to effect, blood or plasma or plasma expander administration when dealing with the severely injured and bleeding patient. This is preferred significantly over the use of crystalloids. There have not been problems with over transfusion or allergic reactions in the patients treated, in the author's experience. This is also recommended and performed in human patients suffering from severe acute blood loss as well. The concern of the function of platelets and the development of a coagulopathy when using dextran or hetastarch as substitutes for plasma has also not been a problem in the author's experience as long as the total amount administered rapidly has not gone over 50% of the patient's normal plasma volume.

Alternative initial fluid replacement with the use of hypertonic saline (7.5%) and dextran 70 (6%) solution [HSDS] has recently been found to be very effective in the treatment of hypovolemic shock induced through blood loss. When the HSDS is infused the hypertonicity pulls interstitial fluid into the circulation very rapidly and effectively. It has also been observed experimentally that the solution acts in some way, possible through some osmoreceptor triggering and neurological input into the cardiovascular system, to stimulate a direct increase in cardiovascular response and resulting cardiac output.

The advantages of HSDS therapy is that only 5ml/kg is required to be infused. This is equal to the infusion of

one blood volume of lactated Ringers solution (90 ml/kg body weight). Because of the relatively small amount of HSDS require, it can be infused very rapidly compared to the infusion of LRS or some other isotonic fluid and provide the same initial response. Because of this small amount the infusion of HSDS can also be effective if given intraosseously (into the medullary canal of either the humerus or femur).

The addition of dextran (or some other synthetic colloid, e.g., Hetastarch) to the hypertonic saline is important to hold the fluid from the interstitial space in the vascular compartment. If is not used the fluid begins to leave as soon as the plasma osmolality is normalized, usually taking approximately 30 to 45 minutes. The benefits of hypertonic saline alone (without the addition of the colloid), have been shown to last no more than an hour. With the colloid added, especially when continued colloid is administered, sustained vascular volume expansion has been observed in experimental studies in dogs, to last 2 to 5 days depending on the colloid. This is in contrast to lactated Ringer's solution (LRS) which, according to some authorities, 75% leaves the circulation and enters the interstitial spaces within the first hour after infusion. It is important to remember that LRS therefore then is NOT truly a plasma volume expander but rather a interstitial volume expander.

Overexpansion of the interstitial space has recently been recognized as a major problem in the resuscitation of trauma patients with crystalloids alone when estimated acute blood loses are over 30% normal blood volumes. Although crystalloids alone, have been used when no other choices (colloid/blood) are available, the price paid is interstitial edema. This is tolerated by many traumatized patients, but also has been shown to increase morbidity and mortality in head and pulmonary injured patients. Therefore, particularly in these cases, blood or colloid replacement is indicated for volume restorative therapy.

Oxyglobin is also a very good "fluid of choice" to use in patients with hemorrhage. Because of it colloid characteristics it stays in the circulation over 20-40 hours. Because it carries oxygen as a hemoglobin molecule as a plasma containing it assists oxygenation substantially. Even giving 2-3 ml per kg will assist oxygenation at a cellular level. Its use is highly recommended.

Fortunately many patients with body cavity hemorrhage following blunt trauma can be managed WITHOUT surgery, provided no hollow visceral disruption has occurred and the patient remains stable after initial resuscitation with counterpressure, colloid replacement, and rest. Very careful monitoring is important in detecting signs of decompensation, indicating further bleeding or bleeding resuming that had one stopped.

In patients with catastrophic hemorrhage or those showing signs of rapid decompensation, rapid surgical approach to the bleeding area must be made. Occlusion of both venous and arterial structures is then done, often done blindly, by simple digital pressure at first. Definitive repair or ligation is then accomplished. If blood can be aspirated and saved it may be used for transfusion in selected cases.

Emergent thoracotomy should be accomplished rapidly. Unless the hemorrhaging area is obvious the pericardium is opened and the heart inspected first to make sure no tamponade exists. Holes are initially plugged with a finger if blood is spurting. Suture on a swaged on needle is used to rapidly close the whole using a simple continuous pattern. Left auricular access for the infusion of blood and colloids/crystalloids can be achieved by grasping its tip with a forceps, placing a Miller's knot or a simple loop around it, cutting a small opening into the tip and advancing feeding tube inside. The loop or Miller's is then pulled tight and tied to prevent blood loss from the auricle from occurring. The suture is then carried around the tube and also tied to prevent the tube from backing out. Blood from within the chest can be drawn up into syringes or into a trap bottle using suction and then administered back into circulation through the atrial tube.

The author has only observed a few patients presented with wholes in the heart in which it was believed there was any chance for survival. None have survived long term but two have been initially resuscitation successfully. Lack of sufficient blood for transfusion was believed responsible for the eventual deaths in each even though autotransfusion was used.

Injuries of the aorta and major vascular branches have also been observed but are also rare. Temporary occlusion with vascular forceps or a loop of umbilical tape, feeding tube, or IV administration tubing is accomplished and then either suture repair (aorta) or ligation (other vessels) is then accomplished. The aorta tears very easily in the dog therefore fine taper swaged-on monofilament suture should be used for repair attempts. Pledgets of fascia harvested from nearby muscular coverings have been useful in stenting the suture and preventing pullout in the author's experience.

Temporary occlusion of the aorta proximal (inferior) to the left subclavian artery is limited to only a few minutes (maximum) while distal to it occlusion can be done for 5 to 10 minutes in most cases. Although variations between patients and their physiologic state at the time of occlusion does not allow definition of a "safe time limit". Therefore occlusion should be limited to as short as possible as the very nature of the immediate need for emergency occlusion of the aorta prevents electrophysiologic monitoring of evoked potentials to indicate when the safe time limit is being approached.

On the high pressure side of the circulation only the aorta has to be repaired. Other thoracic arteries including both common carotids and the left subclavian can be ligated without complications due to the anastomosis through the ventral spinal artery. Due to extensive anastomosis even the brachicephalic trunk can be ligated without complications unless both the vertebral and carotid arteries individually are ligated to prevent the arterial looping required, as both the dog and cat have an a well developed circulus arteriosus cerebri (Circle of Willis). Arterial looping provides adequate protection against cerebral infarction and brain hypoxemia due to poor circulation in the vast majority of animals. Permanent thoracic aortic occlusion leads to paralysis. It has been stated however that when cerebrospinal fluid pressure is decreased by performing a cisternal puncture and removing 8 to 10ml of CSF following thoracic aorta ligation that nearly all animals recover without paraplegia. The same authority states that following ligation in some animals, distal aortic pressure did not rebound but stayed extremely low (below 12 mm Hg). This indicated poor arterial looping and collateral circulation. All these animals died within 60 minutes.

Low pressure sources of hemorrhage can be very effectively temporarily controlled by applying direct pressure. Injury to the vena cava or the brachiocephalic veins should be repaired. Chylothorax and head and neck edema are complications of ligation of the brachiocephlic veins or proximal portion of the cranial vena cava. Repair is also required for injuries to the pulmonary artery or its main branches if that portion of the lung is not removed.

With all vascular repairs the author has the most successful experience when using a continuous pattern with 6-0 to 3-0 polypropylene or polybutester on a fine taper or taper-cutting needle. The use of a fiberoptic surgical headlight and 3-5 power loops to improve visualization are also recommended if available. Ligation has been most expeditiously done using hand ties with 3-0 to 0 silk strands. The use of surgical stapling devices for lung or partial lung resection is another option that allows for rapid removal and secure vascular and bronchial closure.

Catastrophic abdominal hemorrhage requires emergency celiotomy and is often best done following a resuscitative thoracotomy and aortic cross clamping. If it is not done prior, as soon as the abdomen is entered and the blood and fluid present in the distended abdomen rapidly leaves and systemic pressure drops precipitously. However this can be minimized if, as soon as the abdomen entered a hand is inserted and placed on the proximal abdominal aorta and compressed. The hand must be placed cranial to the origin of the celiac artery and this area can be performed by palpating the left kidney, then the adrenal gland, and then putting pressure on the midline just cranial to this area. The crus of the diaphragm can also be palpated and used to locate the proximal abdominal aorta. In severe hypotensive states the aorta is not palpable itself. Following digital occlusion blood flow to the heart, brain and other structures cranial to the site of compression significantly improves. This can be documented if a Doppler blood flow detector is being used. Severe arterial hemorrhage distal to the site of compression will be temporarily controlled.

Because aortic occlusion does not stop severe venous bleeding towels or lap pads are inserted and packed into the abdomen. The packing will help temporary control major venous bleeding. The incision in the abdomen is then enlarged to extend from xyphoid to near the pubis. The packs are parted enough to see where the aorta is being compressed. A window in the paraaortic fascia is made with a curved forceps and a loop of umbilical tape, tape marker attached to a lap pad, or a 3 1/2 to 8 Fr. feeding tube is grasped, pulled around the aorta and held tightened with hemostats. Packs are then removed as suction and inspection is performed, quadrant by quadrant, looking for the sources of hemorrhage. The aortic occlusion is freed intermittently as each quadrant is inspected after severe venous bleeding is first ruled out.

As each bleeding source is found it is temporarily controlled using a vascular occlusion method similar to that used on the aorta only closer applied, e.g., a feeding tube encircled around the splenic pedicle and tightened when a severely bleeding spleen is found. It has been the author's experience that if this method of dealing with severe intraabdominal hemorrhage is not done in this fashion these patients often die by the time the all the bleeding sources are found and controlled. After all major bleeding sights are temporarily controlled, definitive repair or ligation as indicated.

Counterpressure if being used is left in place until the patient is anesthetized, instruments are opened, and the surgeon is gowned and gloved. The counterpressure is then quickly released with ongoing vascular volume support continuing. A rapid clip, and prep and spray of the abdomen with a rapidly acting prep solution is performed ideally in less than 2 minutes. 3% chloroxylinol surgical scrub disinfectant, which has a rapid bactericidal action (99.9% kill of all bacteria in 1 minute) and is also gentle on tissues, is recommended.

Draping should be wide including both inguinal regions and done with impervious draping material. This allows rapid access to the femoral artery and vein if central vascular access is required for volume resuscitation and direct arterial monitoring. The sternum and the ventral half of the lateral chest walls should also be in the field to allow for rapid access into the thorax through a paramedian sternotomy if required for aortic cross clamping. Incision for exploratory celiotomy should be performed through a ventral midline incision extending from xyphoid to pubis. Use of monopolar electrosurgery for hemostasis is highly advised.

In cases with exsanguinating abdominal hemorrhage if the abdomen is extremely distended and under tension then aortic cross clamping is recommended via a left thoracotomy prior to entering the abdomen. This will prevent a severe drop in arterial blood pressure as the abdomen is entered and the tamponade effect is released. A second alternative to thoracic aortic cross-clamping that should always be used in all other cases is to first open the abdomen just large enough to enter a hand without releasing the blood and placing fingers on the proximal abdominal aorta proximal to the celiac artery. This maneuver is performed using the right hand, with the surgeon standing at the patient's right side, by palpating the left kidney, then the adrenal gland and then placing pressure on the aorta on the midline just cranial to this area. With the aorta compressed the blood within the abdomen is aspirated into a trap for potential autotransfusion. The trap can be fashioned from a sterilized chest bottle or separate suction reservoir. The abdomen is opened now partially and sterile towels or lap pads or sponges are used to pack the cavity fully from cranial to caudal. This is done to stop major venous bleeding and compress splanchnic vasculature gently to counteract its vasodilation that occurs when the abdominal pressure is released. During this packing ventilation will be need to be supported with positive pressure breathing and Doppler blood flow will need to be monitored carefully.

The abdomen is suctioned and the packs are removed one by one in a systematic fashion to allow a systematic search for all sources of hemorrhage. The abdominal aortic occlusion is intermittently released as each quadrant is inspected after severe venous bleeding is ruled out. Application of hemostats, vascular clips ligatures or electrocautery is used as required to control each bleeding site as needed. In some organ systems temporarily control may also be done using Rummel tourniquets, bulldog vascular clamps, or other non-traumatic clamps (Satinsky, Cooley, Potts, Doyen). Repacking may also be required. Rommel tourniquets placed on pedicles that are severely hemorrhaging which are associate with the spleen, kidney, or liver can provide temporary control while repair is attempted. Safe temporary occlusion times for various vessels have been defined in the dog under normothermic and normotensive conditions. These are as follows:

• 5-10 min : descending thoracic aorta (30-40 minutes of occlusion maximum without neurologic defects if mildly hypothermic and with corticosteroids)

• 30- 40 minutes: abdominal aorta (again increased time with hypothermia and corticosteroids)

• 20 min max. portal triad (hepatic artery, portal vein, common bile duct), hepatic artery alone,

• 30 – 45 min. splenic artery and vein, renal artery and vein, distal caudal vena cava, iliac vessels, femoral vessels.

If severe hypothermia and dilution and consumptive coagulopathy are present it may be prudent to pack areas that continue to bleed following attempts to control the hemorrhage (called " damage control"). This is particularly helpful in major injuries to the liver, but could also apply to kidney and other highly vascular structures. The area involved is first covered with a blanket of omental pedicle then packing is done with sterile lap pads, bubble wrap or towels. Hemostasis is enhanced further if a sheet of porcine small bowel submucosa (VetBioSISt, Cook Vet Products) is applied to the oozing surfaces before the omentum and pack are applied. Closure of the abdomen is then done while maintaining gentle pressure that was observed to control the bleeding. The packs are removed 2-3 days later after the coagulopathy has been reversed.

Severe bleeding from the cut edges of the diaphragm can occur and is one of the key reasons why acute diaphragmatic hernia should be operated on as an emergency. Tearing of the diaphragm can also be accompanied by tearing of the deep cranial abdominal epigastric arteries and veins and the liver. Recent cases that I have managed revealed more than 1/3 of the patient's blood volume within the abdomen by the time the emergency surgery could be performed (between 6 and 12 hours post-injury). Treatment of the hemorrhage includes reducing the hernia and performing an examination of the vessels, cut edges of the diaphragm and the dome and hilus of the liver. Examination requires a careful look at the mediastinal and lung tissues and if severe bleeding from these areas is noted then extension into the thorax with a parasternal approach is made. Lung bleeding can be arrested with direct suturing, ligation, or stapling. Ligation of the entire lung lobe that is bleeding may be in order if the lobe is significantly injured. Ligation of torn vessels is performed as required. Closure of the diaphragm is done with a pre-placed continuous pattern with polypropylene. Closure of paramediastinal approach is then accomplished after a chest tube is placed and secured to the fascia. Figure of eight polypropylene is used for the closure which encircles the rib and the sternum. Each of these sutures is pre-placed and then tied tightly. A continuous closure of the pectoral muscles then follows. Closure of the subcutaneous tissue and skin is routine.

This is initially controlled with packing. If it the hemorrhage does not stop with packing an intravenous dose of sodium penicillin (120,000 units/kg) or first generation cephalosporin-(40mg/kg) and the hepatic artery isolated and temporarily occluded to remove the high pressure source of bleeding. The antibiotic is necessary to prevent acute anaerobically induced Clostridial hepatic necrosis. If bleeding still continues the portal vein along with the hepatic artery is temporarily occluded (Pringle Maneuver). The cranial mesenteric artery should also be occluded to prevent acute portal hypertension .

If bleeding from the liver is still occurring the source is a hepatic vein. This can be temporarily controlled by placing a tube inside the torn vein approximately the same size as the hole. A purse string suture of 3-0 to 4-0 monofilament suture (on a cardiovascular needle) is then placed around the outside of the hole and as the tube is withdrawn the purse string is tightened and tied. The tube can used to infuse fluid and blood for volume resuscitation which is usually required. Blood can also be collected from the abdomen and immediately reinfused (autotransfused) through the tube.

Crushed liver lobes, that were bleeding prior, are removed by either a modified finger fracture technique, ligation at the base of the liver lobe, or stapling.

With very severe bleeding, if the patient is very cold and coagulation is poor due to traumatic consumption of

clotting factors the best treatment of the placement of omentum over the crushed liver and then packing the area with surgical towels and closing rapidly. This "damage control" method of trying to stop the bleeding requires blood transfusion and a fortitude to close the abdomen with active but slow hemorrhage on-going. The abdomen is closed and the patient is kept very quiet for an additional 12 hours. Gentle counterpressure is applied and blood pressure is monitored. Pressures are maintained from 60-80 and allowed no higher. Re-exploration is performed after the patient’s coagulation has normalized and the patient’s temperature has also normalized. This "limited counterpressure" and "hypotensive resuscitation" can be also tried when no funds are available to explore and arrest the hemorrhage surgically. These animals are kept quiet with neurolept analgesics.

If only mild coagulopathy and hypothermia is present mild liver hemorrhage can be easily controlled with the placement of a layer of omental pedicle and maintained pressure for 10-15 minutes with a lap pad, towel, or bubble wrap. Hemostatic enhancing materials can also be applied prior to the omental layer. The omental layer can also be gently pinched to release endogenous tissue thromboplastin and expose collagen that will enhance coagulation. Superficial lacerations that are not bleeding after the packing is removed do not require suturing. Superficial lacerations that continue to bleed following direct are sutured with 1-0 to 3-0 chromic gut, usually using a mattress pattern. Other alternatives materials that have some success include thrombin - bovine collagen, C-stat, gelatin sponges, and cyanoacrylate (Super-Glue) which are applied in the cracks in the liver parenchyma and then pressure is applied for a few minutes. Suturing with 2-0 to 3-0 chromic gut using a mattress pattern can also control superficial lacerations that are continuing to bleed. Absorbable multifilament sutures lubricated with fat can also be used in place of gut.

Severe liver hemorrhage control can be extremely challenging and is invariably associated with coagulopathy. Fresh whole blood and fresh frozen plasma are commonly required. Autotransfusion is also commonly required. Surgical exposure should be maximized by at cutting along the xyphoid cartilage and placing a laparotomy pad dorsal to the liver to help hold it up. Rarely sternotomy or parasternotomy will be required if the large hepatic veins are injured. In these cases the hand is inserted into the thoracic cavity and pushed into the liver hilus forcing the vena cava to be compressed against the inflow area where the hepatic vein dumps in. This prevents retrograde hemorrhage through the injured hepatic vein opening allowing visualization after inflow into the liver after temporarily occluding the portal vein and hepatic artery (the Pringle maneuver). The epiploic foramen is found and just ventral to it are the portal vein, hepatic artery and common bile duct. All three structures are occluded either digitally with thumb and fingers, tape Rommel tourniquet, or atraumatic vascular clamp. Antibiotics must be administered intravenously prior to occlusion of any vessels to prevent ischemia and resident bacterial growth into liver parenchyma. In the normothermic patient the Pringle maneuver can be performed for 15 minutes. In hypothermic patients who have been given corticosteroids (30 mg/mg methylprednisolone) occlusion has been maintained for 30 to 40 minutes without postoperative complications. The opening into the hepatic vein will be able to be visualized and suture closure (5-0 polypropylene) is accomplished. These are the worse injuries I have had to deal with concerning hepatic injury leading to major life-threatening hemorrhage with most of the patients with this injury dying.

To visualize deeper vessels that are bleeding, a finger fracture technique, facilitated by the use of the back of a scalpel handle can be used to used to dissect throughout the liver lobe. The Pringle maneuver is performed first. Suction and the use of irrigation helps to visualize the vessels. Curved hemostats or vascular clips are then applied to the bleeding vessels. Ligations are done with hand ties using nylon or silk suture. An omental pack is then applied into the depths of the liver wound and loosely sutured in place. Crushed liver lobes can be removed by the finger fracture technique, ligation at the base of the liver lobe with a modified Miller's knot with slow release and flashing, or stapling. Resection of devitalized liver segments can also be done using a CO2, Diode or Nd:YAG laser or ultrasound dissector or electrosurgery. Thoughts on the management of subcapsular hematomas are divided; the risk being delayed rupture if the hematoma is not explored, and the risk of massive exsanguination if they are opened. Observation of the hematoma for expansion or evidence of ischemic-necrotic tissue would indicate the need to take the risk of opening the hematoma.

Splenic hemorrhage should be controlled initially with direct pressure and packing. The splenic pedicle can be occluded using gauze wrapped around the pedicle or a Rommel tourniquet. Vascular clamps can also be used. Forrester sponge forceps with gauze used between the jaws can be used as a substitute for a vascular clamp. Lacerations can be controlled with sutures and hemostatic agents can be used to control oozing. Stick ties are often all that is required with mid body or small lacerations. Even larger lacerations will often seal if omentum is incorporated into the suture. Ligation of splenic vessels can be performed with hand ties of 0 to 3-0 silk. Studies have shown that only 6 to 8 double ligatures are required in splenic removal. In fact I have commonly used only 5 clamps (Rochester Peans or Carmalts) to perform a rapid splenectomy. However in cases where consumption of platelet and coagulation factors has occurred ligation of the omental pedicle will also be necessary. Care must be taken to maintain pancreatic blood supply. Gastric decompression postoperatively may be required. There are MANY spleens and livers that stop bleeding with outside pressure and immobilization and keeping arterial pressures marginally low for 30 minutes than gradually increasing.

Management is generally limited to conservative examination without operative exploration if the source of the hemorrhage is not obvious and the retroperitoneal space is not expanding as generalized abdominal exploration is being performed. In unstable hematomas with expansion of the retroperitoneal space then the retroperitoneum must be opened and explored to identify the source of the hemorrhage. This is recommended only after the aorta is cross-clamped proximal to the hematoma area. This is important to assure control of arterial hemorrhage which could become brisk and prevent visual inspection as required to identify the source of the bleeding.

Aortic cross clamping can be done with the use of a vascular forceps or tape tourniquet. A substitute for the vascular clamp may be used as well; padded or unpadded or rubber sheathed Allis tissue forceps, Forrester sponge forceps, or intestinal occluding forceps. Occlusion can continue safely for at least 30 minutes. During occlusion the hematoma is carefully and gently evacuated and the source of bleeding found and ligated.

If profound arterial hemorrhage occurs, the aorta can generally be ligated if distal to the kidneys. However long term renal compromise and rear limb ischemia is a potential complication, especially with blunt trauma and contusive injury to collateral vessels.

If the retroperitoneal hematoma found at the time of exploration is not expanding then it may be elected not to open the retroperitoneum. These hematomas are commonly due to severance of multiple small veins and arteries that stop bleeding spontaneously. The few cmH20 of pressure that builds up inside the retroperitoneal space from this hemorrhage is sufficient to control it. Opening the hematoma up in these cases is not recommended as this could cause recurrence of the hemorrhage. Rather it is recommended to treat by enforcing strict rest and using pelvic limb and pelvis external counterpressure, performed with the use of a pneumatic antishock garment (canine or human pediatric) or with the application of a circumferentially applied stretch dressing (ace wrap) only snug enough to feel mild pressure on a hand placed under it after its application on the body. This is maintained for 24 hour then gradually released. If pressure in the pneumatic device used can be measured it should be limited to 20 to 40mmHg when maintained for 24 hrs. This amount of pressure and time has also been successful in the definitive control of serious renal hemorrhage following percutaneous biopsy.

Treatment with tranquilization and enforced rest is also very important and can not be over emphasized, particularly during the first 24 hours following the injury, to prevent reoccurrence of the hemorrhage. Small intravenous doses of tranquilizer/narcotic combinations as needed are helpful in controlling the patient's activity, pain, anxiety, and arterial hypertension that may occur in these animals.

If a hematoma is observed in the inguinal region and it is determined that it is not expanding and the patient remains stable it is also recommended NOT to surgically explore these as well. Blunt or tearing penetrating trauma, as occurs in dog fights, frequently causes muscular and tendon injury that leads to herniation of small intestine and/or bladder. If this is determined by careful examination or plain film radiographs, investigative and reparative surgery should not be delayed long, e.g., only as matter of hours. Long delays are not recommended because in the author's experience many times serious vascular compromise to the herniated and injured tissues is often present, with death due to endotoxemia being the result if surgery is delayed.

Most retroperitoneal bleeding can be managed conservatively as the hematomas are usually caused by hemorrhage from multiple small arteries and veins and bleeding will spontaneously resolve. If the hematoma is expanding it will require exploration. Nephrectomy should be reserved for signs of ongoing uncontrollable hemorrhage or avulsion of the kidney. If no coagulopathy is present direct pressure to the bleeding area for 10 to 15 minutes may be all that is required to obtain definitive control even if the entire kidney is split open. Cruciate sutures can be used for small lacerations. The renal pedicle can be occluded for 30 minutes if required. A partial nephrectomy can be performed with closure of the pelvis and sutures running from capsule to capsule to control bleeding and urine flow. A total nephrectomy can be performed with double ligation of the pedicle. Tears into the vena cava or aorta which must be sutured with closely placed cruciate or simple continuous sutures with fine (4-0 to 6-0) monofilament material on swaged-on cardiovascular needles.

Other vascular or organ injury resulting in catastrophic hemorrhage is definitively managed using ligation, electrosurgery, ligature, staples, or suture as indicated. The use of cyanoacrylic glue placed into the bleeding bed of a hemorrhaging area, after temporary occlusion and drying of the bed, has also been used very effectively, including hemorrhage from the pancreas, liver hilus, spleen, lung hilus, and pelvic veins when low coagulation factors and platelet numbers are present as a result of the trauma, extensive autotransfusion, transfusion of stored blood, and disseminated coagulopathy.

Commonly affecting the large breed deep chested breeds gastric dilatation and volvulus syndrome has the potential to be a life threatening problem. Progressive gastric distension leads to pressure on the vascular system especially the venous system compromising venous return to the heart thus leading to inadequate preload and shock secondary to inadequate stroke volume. Pressure on the diaphragm caused by a progressively dilating stomach may compromise lung expansion and lead to ventilatory compromise. Vascular compromise of the circulation to the stomach itself may lead to tissue ischemia, release of endotoxins into the circulation and ultimately to the release of cytokines and SIRS.

There are many inciting events that can "cause" GDV. GDV is often associated with a disease processes that involves ilius, anxiety, anatomy of a large deep chest, and age enough to see the suspensory apparatus of the stomach be "stretched " out. Most animals that have a GDV are middle aged (6year or greater). The disease of GDV was first described in humans.

Diagnosis is commonly made by observing a dog that is restless, attempting to retch non-productively and perhaps has rapid abdominal distension. Due to the fact that the GDV mainly occurs in the deep chested dog the abdominal distension may not be evident until late in the disease. In early cases the gas distended stomach may be detectable on percussion of the cranial abdomen. On examination the dog may be in hyperdynamic shock or may be in a stage of decompensatory shock. As such findings are variable from tachycardia, tachypnea, bounding pulses and injected mucous membranes to collapse, respiratory distress, weak thready pulses.

Immediate treatment should consist of oxygen if the dog is showing any signs of shock, and volume replacement with crystalloids and synthetic colloids started. Recent studies point to the value of hypertonic saline mixed with a colloid and given at 5 –7 ml/kg as a bolus and then reassessing. Hetastarch or Oxyglobin should be considered to maintain BP and flow. ECG should be monitored, as these dog are prone to ventricular arrhythmias. The stomach should only be decompressed after volume replacement has been started due to the potential for worsening the hypovolemic shock. Rapid onset corticosteroids are usually given at shock doses (dexamethasone sodium phosphate at 4-8 mg/kg iv or methylprednisolone sodium succinate at 15-30 mg/kg iv) and broad spectrum antibiotics started. However there is NO good controlled randomized blind study of a significant number of patients that has been done to conclude that steroids of any kind make a significant difference in survival.

A right lateral radiograph should be taken in most cases if there is any doubt. On occasion the volvulus will not be evident on the right lateral in which case if there is a high index of suspicion a left lateral radiograph should taken. A characteristic shelf sign with compartmentalization supports a diagnosis of a gastric volvulus. Barium placed by an NG tube may have to be administered to define the location of the stomach. Coagulation should be monitored as these patients are at risk for DIC. Blood pressure should be monitored. A thoracic radiograph on any patient > 5 years is also recommended.

passed on a twisted stomach. It is also possible to pass a stomach tube through the wall of an ischemic stomach and excessive force should not be used. Following gastric repositioning an incisional gastropexy is accomplished. A nasogastric tube is inserted to prevent re-dilation postoperatively. In cases that have much food material in the stomach the stomach is massaged and the food removed via a large orogastric stomach tube in which water is added to dilute the food material. In cases that have very thick or very large amounts of food material including "chuncks" the stomach is opened and all the food material is dumped out and into a basin. The stomach is closed routinely with two continuous closure patterns. An inverting pattern on the second closure can also be used and is recommended if peritonitis is also present or the stomach had previously ruptured. This is a "serosal patch" and helps prevent leakage of the gastric incision line.

When the stomach is returned to its normal anatomic position the color of the stomach is observed carefully. If necrosis with a dark blue purple color persists then the area involved, most commonly the greater curvature section, is removed and closure is accomplished. Closure is done with either simple continuous polypropylene in two layers or an automatic stapling system is used (United States Surgical TA 90) which applies two staggered rows of 4.2 mm stainless or titanium b shaped staples along a 90 mm section. The later method is faster but can not be used in very edematous stomachs because the staples pull out. If resection is required a gastrostomy tube is usually recommended to be inserted to provide an access of continued decompression postoperatively. It is also used to medicate the mucosa with Sucralfate and gruel food and water. The tube is placed through a mucosal purse-string in the antrum incision that is used for the incisional gastropexy. A straight plain 12-20 Fr. red rubber feeding tube is placed through the muscoa purse-string and the purse-string is tied. A seromuscular stitch is placed next to the tube exit site in the stomach and encircled around the tube and tied to prevent the tube from migrating. The incisional gastropexy is then completed with 0 to 1 polypropylene as a simple continuous pattern that closes first the dorsal gastric to abdominal wall incision lines. The submucosa of the stomach and the fascia of the abdominal wall must be grasped with each bite. The suture is placed loosely and then drawn tight to ensure good placement and a tight water tight closure respectively.

A jejunostomy tube is placed for feeding if a portion of the stomach had to be resected. The patient is then fed by this tube postoperatively as a continuous rate infusion. The abdomen is irrigated and closed IF the contamination is not a concern. With gastric rupture the abdomen is generally left open with only a back and forth suture pattern. These dogs will take three to four days before its generally time for the abdomen to be closed.

Postoperative Treatment:

This involved around the clock monitoring and supportive care. Frequently arrhythmias are a problem after the first 24 hours post GDV rotation back to normal.

Blow By Oxygen Administered As ASSESSMENT (Physical Exam) is completed

Gastric Tympani Present and Gastric Distension suspected, Assess Shock

IV Catheters (two) Large Bore (14 gauge ) in the cephalic veins

Plasmalyte Bolused (40 ml/kg mini) or 5 ml/kg Hypertonic Saline and Hetastarch begun

Radiograph the Abdomen and Chest (Right Laterals) and see Double Bubble

If Severe Distension perform gastrocentesis with long 14 gauge needles or catheters

If Unsure pass an NG Tube - administer Barium (2-3 ml/kg) and re radiograph

Confirmed cases induced with Ketamine/Diazepam & begin positive pressure ventilation

Clip and Prep for Wide Exploration from Xyphoid to Pubis

Aspirate Air from NG tube passed and reposition stomach into normal position

Pull Pylorus ventrally from the right and push the body dorsally with right hand to the left

Explore; Remove Spleen at the least bit of thrombus formation or hemorrhage

Assess the Gastric Wall for evidence of necrosis

Place NG tube (unless much solid material present in the stomach – if so do gastrotomy

Perform an incisional gastropexy if the stomach wall appears OK – Incision G-tube if not

The dog is weighed and assessment of dehydration and volume depletion is made. Assume the dog to be a minimum of 10% depleted. Assess blood flow and pressure with a Doppler and as the monitoring is continuing, placer an IV catheter in the cephalic vein (by mini-cutdown if needed) and provide a warm saline enema. At least 30 ml/kg of saline should be infused. This is to evacuate the colon of endotoxin and pathogenic bacteria and virus. Run the warm saline (home made = 1 tsp salt to a quart of water) until the effluent is clear. This is repeated AS NEEDED TO KEEP THE COLON EMPTY OF TOXIC FECAL MATERIAL (NO SMELL AND CLEAR). The infusion of colloid (6% hetastarch) and a crystalloid (the hetastarch is in saline)and this is the crystalloid. Give as needed to establish good Doppler blood flow and a minimum of 70 mm Hg systolic BP. Begin supplemental oxygen via a nasal oxygen if the puppy is very weak. Place a NG tube and aspirate the stomach, removing all the toxic gastric fluid. Begin IV cefazolin at 40 mg/kg (first dose is double the routine 20 mg/kg dose). Provide Plasmalyte or Normosol R which contains Mg ions rather than the Ca containing ones such as lactated Ringers solution. Generally this is delivered at 2-3 ml/kg/day to start. Monitor JVDT and JVRT, HR, CRT, lung and heart and bowel sounds, and Doppler flow and pressure during fluid administration. Begin trickle feeding after all the stomach fluid is removed. A trickle feeding formula useful is 10% -20% glucose, 4% glutamine, and electrolytes and glycine (a commercial rehydrating fluid can be used as well). Provide human albumin 25% at 0.3 to 1 ml/kg/hr depending on assessment of vascular volume to keep plasma albumin levels greater than 2 gm/L. Provide nursing care as needed. Monitor glucose and electrolytes daily as well as CBC. Most will recover with this protocol (>95%) in my experience; however this is more costly. If clients can not afford this level I recommend they provide the nursing care. In these cases I send them home with all the tubes and they care for the dog (on an intensive basis)

Dennis Tim Crowe, 1982 ACVS Surgical Forum

Recommending surgery as part of the definitive treatment for severe pancreatitis in veterinary medicine is not new. I continue to maintain that whenever any abdominal organ or part of the organ is necrotic it should be removed surgically as rapidly as possible and this includes the pancreas of both dogs, cats and other species. Unfortunately I have not had an opportunity to prove my case with a blind randomized clinical investigation and the reporting of the findings. The only "proof" I have that what I recommend is true comes from the following:

1. Data from rats indicating that removing inflamed and necrotic pancreas improves survival.
2. Common sense and basic surgical principle that dictates that removing necrotic tissue before it causes severe secondary SIRS and MODS is a good idea that may lead to increased survival.
3. Data from handful of severe necrotizing pancreatitis cases (accumulated from 1980 to 2000) that I have personally managed as both the emergency and critical care veterinarian and as the surgeon that have survived; and comparing this to similar cases handled by others that did not receive surgery and went on to die and where I was present to see the gross necropsy.

To understand the reasons behind the recommendation that severe pancreatitis is often a surgical disease we will first review the pathophysiology of pancreatitis. I will then concentrate on the key areas of management that I feel must be addressed, as alluded to earlier, to provide the highest chance of survival possible. These are a continuum and begins with 1. Making an early and accurate diagnosis that indicates the need for surgical intervention by utilizing the patients EARLY clinical course, laboratory analysis, and specifically diagnostic peritoneal lavage and providing medical support to hold the inflamed pancreas in check if possible with the early diagnosis of severe complicated panreatitis; 2. Surgical management (involving assessment of the pancreatitis, resection of diseased portion, irrigation and drainage, and placement of a jejunostomy for postoperative feeding); 3. Postoperative care involving fluid and electrolyte monitoring and administration, nutritional support, pain control, antibiotic coverage, respiratory support, etc.

It is generally believed that severe acute pancreatitis has many inciting causes, all of which activate the pancreatic digestive enzymes within the cells of the pancreas it self. Abnormal fusion of lysosome and zymogen granules occurs, probably due to intracellular transport, storage or exocytosis of zymogen granular contents. The activation of the trypsin and other proteases within the zymogen granules leads to intracellular destruction and a spillage of its contents to the surrounding interstitium. Superoxide radicals are generated from the autolysis of the pancreatic cells as well as the abundance of neutrophils that become activated and accumulate in the area. As the neutrophils disrupt more proteolysis and membrane disruption occurs which leads to significant necrosis (autodigestion) of pancreatic tissue and this leads to progressive extrapancreatic tissue necrosis and suppuration as well.

Experimental and clinical studies indicate that activation of progressively large amount of proteases and phospholipases within the gland and the production of increasing amounts of cytokines and superoxide radicals, especially hydroxide and peroxide is the reason mild edematous panreatitis progresses to hemorrhagic and then necrotic pancreatitis. The systemic uptake of all of the products that are liberated in the process then lead to multisystem involvement. The protective plasma protease inhibitors such as alpha-macroglobulin are consumed as these the necrotizing process continues. As the alpha-macroglobulins are depleted death occurs from acute disseminated intravascular coagulation and shock as the circulating proteolysis and cytokines activate the quinine, complement, coagulation, and fibrinolytic cascades.

Grossly pancreatitis progresses from that of edema and mild sponification and a few one millimeter sized abscesses to that of severe edema, numerous areas of sponification and many small abscesses. Then it progresses to hemorrhagic pancreatitis, localized peritonitis and edema of the surrounding tissues and advances to necrosis, larger abscesses, and the formation of very firm sections of cellulitis and pancreatitis (a phlegmon). In some cases bacteria translocate from the duodenal lumen and generalized peritonitis, bacterial abscessation, secondary biliary blockage and necrosis of the ventral aspect of the duodenum occurs. In the most severe cases the entire panaceas becomes involved with abscessation and necrosis. In some cases necrosis occurs where fat normally accumulates in the retroperitoneal space and falciform ligament.

Spontaneous pancreatitis appears to have a number of mechanisms that play a role as "inciting causes". In most cases it is suspected that a combination of the these are often involved. These include the following:

1. Malnutrition; This had been reported to cause pancreatitis in humans. Pancreatitis has been reported after the beginning of refeeding after prolonged fasting, particularly with diets involving large amounts of protein and fat that are sources of omega six fatty acids (which have been used to induce experimental pancreatitis in animals by intraductal injection).

2. Stress; This has been clinically observed particularly in obese dogs and cats, particularly with the addition of exogenous corticosteroids and in those with gastrointestinal mucosal hemorrhage.

3. Hyperlipidemia or hyperlipoproteinemia; Familial hyperlidemia in human has been documented to be associated with frequent episodes of pancreatitis. There is also clinical and experimental evidence in animals that panceatitis can occur with dietary induced Hyperlipidemia, particular in miniature schnauzers with ideopathic hyperlipoproteinemia.

4. Drugs: The use of a number of drugs have been associated with the onset of clinical pancreatitis. These include thiazide diuretics, furosemide, azathioprine, L-asparaginase, sulfonamides, tetracycline, lipid emulsions used in parenteral nutrition, and corticosteroids. Controversy exists as to the casual relationship of corticosteroids and pancreatitis and further research needs to be accomplished in this area to confirm the causal relationship. However this clinician has seen a multiple number of moderately obese nervous dogs or dogs under stress following trauma that were treated with corticosteroids and developed severe pancreatitis.

5. Trauma: Although the reports are rare I have personally seen a number of cases that developed rather severe panceatitis leading to death in dogs that sustained blunt injury to the abdomen that had caused other intraabdominal injury that required surgery. It is theorized that the trauma caused enough cellular disruption that enzyme activation and liberation occurred leading to microvascular thrombosis and ischemia.

6. Postsplenectomy: Because the pancreas receives a significant amount of its blood supply from vessels originating from the splenic artery cases of secondary pancreatitis have occurred when, through splenic manipulation and ligation the blood supply of the pancreas was compromised.

7. Postpanceatic manipulation biopsy or resection of pancreatic neoplasms; Although rarely reported pancreatitis has been observed in these situations. Most have been mild cases. This has caused some surgeons to shun from performing any type of surgery on the pancreas for fear of causing life-threatening panceatitis. With careful manipulation however it has been also documented both experimentally and clinically in dogs that induced panceatitis is rare.

8. Hypercalcemia; Panceatitis has been documented in dogs and humans suffering hypercalcemia associated with primary hyperparathyroidism and in cases of iatrogenic hypercalcemia. Hypercalcemia should be avoided as in high concentrations calcium has been shown to enter cells and activate intracellular enzyme systems.

9. Duodenal Reflux; Severe panceatitis has been observed both experimentally or clinically associated with duodenal obstructions induced by ligation, and those related to foreign bodies, masses and severe edema or duodenal smooth muscle hypertrophy. Although the normally present anti-reflux mechanism, made up of specialized duodenal/ductile smooth mucosa, is very effective in most cases, when high duodenal lumen pressures occur the mechanism may fail. The reflux of duodenal fluid activates the trypsinogen to trypsin and other proteases liberated from the pancreas. Edema of the smaller ducts leading from the pancreas occurs and this in combination with enteropeptidase, activated pancreatic enzymes, bacteria, and bile that is trapped within these ducts lead to progression. Recently (January, 1996) I had a cat in which I operated that had severe pancreatitis. It was evident that bile looking fluid was present throughout the pancreatic tissue that was still recognizable as pancreas.

10. Miscellaneous; Many other clinical conditions have been associated with the development of severe pancreatitis. Although rare these conditions include intervertebral disc disease syndrome, scorpion stings, uremia, biliary calculus, cholangiohepatitis, hepatic lipidosis, biliary neoplasms, pancreatic neoplasms, and direct accidental injury where the main pancreatic duct is opened and pancreatic secratory fluid leaks freely around the pancreas.

Animals with acute pancreas are usually presented because of depression, anorexia, vomiting, and in some cases, diarrhea. In severe cases associated shock and collapse may be present. In other cases the signs they have are very vague to almost nonexistent. Some animals with severe panceatitis will exhibit signs of cranial abdominal pain and even a "praying" position. Other s will NOT EXHIBIT ANY PAIN or discomfort. Occasionally the only clinical signs the patient exhibits are from systemic complications, these include jaundice, respiratory distress, acute pelvic limb paralysis or acute mentation changes (secondary to cerebral infarcts, cord infarcts or aortic thromboembolism), bleeding disorders, and cardiac dysrrhythmias.

Radiographs often reveal increased density, diminished contrast, and granularity in the right cranial quadrant, displacement of the stomach, widening of the "angle" between antrum and descending duodenum, displacement of the descending duodenum to the right with gas patterns in the same duodenum. The subjective loss of visceral detail in the cranial abdomen is probably the most common radiographic sign observed. Ultrasonic interrogation of the cranial abdomen will also be helpful in some cases. The appearance of mass effect within the pancreas as well as cystic area, abscess (complex cystic regions), edema, and free intraabdominal fluid are occasionally observed.

Although a leukocytosis with a left shift is commonly observed, in some cases no changes in white cell number or types is observed in confirmed cases of severe pancreatitis.

Assays of pancreatic enzymes in serum provide specific tests for pancreatitis. Amylase and lipase are elevated in my experience in approximately 75 to 85 % (less in cats) of the cases that I have confirmed at surgery or at necropsy. This brings me to the discussion of what appears to be the best test to confirm pancreatitis at our institution.

Diagnostic peritoneal lavage (DPL) has been used and documented in a preliminary paper to be an effective, accurate, and simple to perform test for the determination of acute pancreatitis complicated by necrosis, abscessation, or bacterial infection (Crowe DT : Diagnostic Paracentesis Techniques: Clinical Evaluation in 129 Dogs and Cats, JAAHA 20:223-230,1984) Patients with pancreatitis or injury had amylase levels in the lavage fluid that were higher than the peripheral blood and microscopic examination of the fluid revealed degenerating white blood cells, most being hypersegmented neutrophils. If bacteria were seen in the WBC's present in the lavage fluid a bacterial peritonitis has bee confirmed over 95% of the time at surgery or necropsy. Patients selected to have an exploratory are largely done based on the results of lavage along with clinical signs.

DPL is performed using a peritoneal dialysis catheter (Abbott, McGaw) or lavage catheter ( Arrow, Cook), or a feeding tube with added side holes advanced through a hypodermic needle placed through the skin and abdominal wall. In cats and small dogs a 14 gauge peripheral vein catheter with added side holes can also be used. Warmed sterile physiologic salt solution (lactated Ringer's solution, Plasmalyte [Baxter] or saline) is introduced into the peritoneal cavity as rapidly as possible until 22 ml/kg body weight is administered. The patient is then moved gently from side to side to disperse this fluid and the administration set then placed lower than the patient. As the fluid returns into the administration set, when the fluid appears consistent in color and turbidity, a sample is collected for analysis (chemical analysis to determine amylase, lipase, alkaline phosphatase, bilirubin, and urea nitrogen). A WBC count and differential of the lavage fluid is also indicated, particularly if repeated lavage is going to be used to help make the decision concerning the need for surgery. Centrifugation a collection of the sediment is required for the cytologic exam of the lavage sample. Plasma is added to the lavage fluid (1:1) before centrifugation. This helps preserve cellular morphology and obtain a better concentration of cells on the slides as they adhere better to the slides surface. If plasma can not be used the sample must be spun down immediately and the sediment spread in the slides within 20 to 30 minutes of collection to avoid cytolysis from the use of a severely hypo osmotic fluid that the cells are suspended in.

Based on experience the following are lavage result criteria that would indicate that surgery is recommended (need at least two of the criteria fulfilled):

WBC count of the lavage fluid......> 20,000, increasing with repeated lavage

Differential of the lavage fluid...... predominant cell is neutrophil (>90%), segmented

Cytology of the lavage fluid.......... intracellular bacteria, hypersegmented and vaculated WBC

Amylase of the lavage fluid.......... > 200 i. u. activity, increasing with repeated lavage

Lipase of the lavage fluid.......... greater than the lipase in the serum, increasing when repeated

Ultrasound Investigation - This has become a relatively reliable tool for those cases that reveal significant changes in the pancreas but it still misses many cases that are early , only show edema or are difficult to image due to gas and location. The more "high dollar" the ultrasoiund unit is and the more experience that operator has the more accurate the tentative diagnosis of pancreatic pathology.

Immune-Tests – A radioimmunoassay has been developed to determine serum concentrations of feline and canine trypsin-like immunoreactivity. Unfortunately it is sensitivity and specificity ranges reported are between 33-89% and 56-89% respectively with poor association of the test with the acute necrotizing type. Feline pancreatic lipase immunoreactivity testing has been recently validated to be at 100% for both sensitivity and specificity.

Advanced Imaging (MRI and CT) – When available these modalities may be of value in the diagnosis of pancreatitis and secondary lesions (abscess, cysts, etc.) My experience is limited however in this area.

As quoted from the Third Edition of Textbook of Veterinary Internal Medicine "Clearly there is no widely available ideal test or combination of tests for the diagnosis of acute pancreatitis, and in the absence of direct examination of pancreatic tissue, the diagnosis can only be tentative.....If gross or histopathologic conformation of the diagnosis is required, or the possibility of other abdominal disease is to be eliminated, it is important that attention be given to (performing).... general anesthesia and surgical exploration of the abdomen." (Williams, DA: Exocrine Pancreatic Disease in Textbook of Veterinary Internal Medicine, Disease of the Dog and Cat. 3rd Ed. Ettinger SJ (ed), W.B. Saunders Co., Philadelphia, 1989, pp 1528-1554).

1. Fluid Balance: Aggressive support the patient with pancreatitis is required to maintain fluid and electrolyte balance. This generally requires continuous rate intravenous infusion of a crystalloid; Using a replacement formula to rehydrate the animal and replace lost fluids and electrolytes from vomiting, diarrhea, third spacing, and using a maintenance formula to supply daily water and electrolyte metabolism requirements. To judge the amount of fluids needed the following should be monitored; urine output (keep output at least at 1/2 ml/kg/hr in cats, 1 ml/kg/hour in dogs, central venous pressure (keep pressure at 3-7 cm H20, arterial pressure (keep levels at normal or slightly above normal; giving fluid challenges initally to see if hypotension is responsive to it if ABP is below 100 mm Hg systolic or 50 mm Hg diastolic.

2. Electrolyte Balance: Electrolytes (K, Na, Cl, and Ca ionized, HCO3) should be monitored at least daily during the acute stage of the disease. Potassium frequently requires intravenous supplementation in the daily fluids to provide at least 2-4 mEq/ kg/day. Levels should be observed carefully. Research in humans has shown that total calcium levels can not be relied upon to determine the ionized calcium concentrations. Therefore ionized levels need to be determined using an ion select electrode (Nova STAT 5, i-STAT, distributed through SDI). Calcium should NOT be supplemented unless ionized levels are below 50% of normal, less than 2 mmoles/dl or the patient is exhibiting clinical signs of tetany. Supplementation to maintain serum calcium levels near normal have been associated with an increase in oxygen radical production and subsequent cellular injury

3. Plasma Albumin Levels Maintenance: Albumin levels MUST be maintained above 2.0 to 2.5 grams/dl (or Total Plasma Solids above 4.5) and is done with the administration of plasma; preferred over the administration of human, canine, feline or bovine albumin. Plasma also provides a source of alpha macroglobulin which binds the activated and liberated proteases. Observations have indicated that in severe pancreatitis there is a marked consumption of plasma protease inhibitors and depletion of these inhibitors is rapidly followed by acute DIC, shock, and death. We recommend monitoring PCV/TS every 8 to 12 hours and that plasma be administered as an infusion following the addition of heparin (2 units/ml) to it 30 minutes prior to its delivery. Packed red cells or whole blood should be administered as needed to maintain PCV above 25% but kept below 40%.

4. Synthetic Colloid Administration: Dextran 70 or Hetastarch (hydroxyethyl starch) 6% should be administered to improve microcirculation blood flow and help in the prevention of endothelial, interstitial and intracellular edema. Hetastarch (Dupont) has a much larger molecular weight and size than that of albumin (weight averages; 400,000 daltons for Hetastarch vrs. 69,000 d for albumin, and size averages; 350 angstroms for Hetastarch vrs. 80 angstroms for albumin). Normal capillary intracellular clefts ("pores") that have an average size of 60 to 70 angstroms tend to "enlarge" in their size with shock and pancreatitis. This contributes to the loss of intracellular fluid, electrolytes, albumin and key small proteins (protein C, antithrombin 3). As these small protein are lost their is a tendency to see microvascular thrombosis. As albumin is lost capillary oncotic pressure drops (a 50 % drop in albumin from normal decreases COP to 33%. This level of COP decrease corresponds to significant development of interstitial edema. As fluid leaves the microcirculation significant slugging occurs and flow is drastically decreased. This contributes to the development of intravascular microthrombosis, particular in the areas of inflammation (e.g., the pancreas). To counter these effects Hetastarch is administered as a bolus to support vascular pressures back to normal or slightly above normal (up to 15 ml/kg) and then is administered as a constant rate infusion (1-2 ml/kg/hour). This clinically has been shown to support the vascular systems integrity, prevent worsening of endothelial cell, general cellular, and interstitial edema, Dextran and Hetastarch also "coat" platelets and help prevent microthrombosis.

5. Glucose: Glucose should be monitored at least every eight hours and maintained at between 110 and 150 mg/dl. Frequently either additional glucose will be needed to be added to the intravenous fluids to maintain levels in the target range if severe sepsis or system inflammatory response is accompanying the pancreatitis (common). In some cases insulin will be required (generally needed with the addition of partial parenteral nutrition which is started within 12 hours of admission). As a rule of thumb 0.1-0.2 unit per kg body weight of insulin per 24 hours of fluid support is required in cases where blood glucose levels are above 250 - 300 mg/dl. If insulin is added to the fluids than blood glucose should be monitored every 4 hours and done as required if any neurological signs are observed.

6. Nutritional Support: Nutritional support should begin within 12 hours of admission as a goal. The longer this support is not provided the higher the incidence of mortality in severe illness. Twelve hours is used as the maximum cut off period because this is generally the amount of time taken to provide fluid support to regain hydration and to see how committed the owner is to the entire supportive process as the products we use cost approximately 35.00 per liter (minimum) and once opened they must be used within 24 to 72 hours. The products referred to are partial to full parenteral feeding formulas (3- 4.5% amino acid and maintenance electrolyte mixtures and 10-20% soybean oil emulsion suspensions). Most are best given through a central venous catheter. Partial parenteral formulas can be given by peripheral catheter if a central line is not able to be used (due to cost constraints). ProcalAmine (McGaw) which is a solution containing 3% amino acid, 3% glycerin, and maintenance electrolytes is commonly used a partial parenteral nutritional support product, given at a rate of 2-4 ml/kg/hr as a constant rate infusion. Due to its high osmolality it can not be given any faster or serious central nervous complications will result.

7.Hyperbaric Oxygen Therapy – In recent years we have noted dramatic resolution in the clinical manifestations of pancreatitis in both dogs and cats with the EARLY use of hyperbaric oxygen. Since at least a part of the pathophysiology is related to the development of pancreatic ischemia it makes common sense to provide oxygen to the involved tissues. A recent study published in Critical Care Medicine in laboratory rats in which pancreatitis was inducted showed a beneficial effect with the early use of hyperbaric oxygen therapy (HBOTx)of 2 ATA of 100% oxygen given for 1 hour. I and others (Personal Communication: Ron Lyman, DVM, DACVIM) have seen resolution clinically in both dogs and cats after HBOTx.

As a general rule we use a "combination approach"...providing only trickle feeding (0.1 ml/kg/hr ) with a Nasogastric tube (NG tube) of an electrolyte solution containing an isotonic mixture of electrolytes and 2-3 % glucose. This is done to prevent gastric stress ulceration (common in patients with severe pancreatitis) and clinical research suggests this does NOT stimulate pancreatic secretion. This solution is administered with fluid pump and is colored with blue food coloring to detect it in vomitus or aspirations. This form of "microenteral nutrition" is only continued if hourly aspirations on the NG reveals NO accumulation of this fluid in the stomach and NO vomiting of the material is detected.

Patients that have surgery have an advantage over those that do not in that a jejunostomy catheter is able to be placed and then feeding is done as a constant 1-4 ml/kg/hr infusion of a monomeric liquid diet (Alitraq, Ross Labs) that is specifically formulated for human patients that have gastrointestinal dysfunction. We have also used a polymeric liquid diet (Clinicare, Abbott Labs) provided periodic aspirations reveal no residual amounts accumulating in the small intestine. The advantage of J-tube feedings is that this does not stimulate pancreatic secretion if reflux and small bowel distension does not occur (which is rare). The feeding is commenced as soon as surgery is completed. Two to three days may be taken to reach a daily intake of 75 to 85% of the calculated caloric and protein requirements (48 Kcal/kg/day energy in the form of carbohydrates and limited fat [20% of caloric distribution], and 6 grams of high quality protein/100 kcal required/day).

7. Other Important Keys: Other important keys to the successful management of the patient with severe pancreatitis include: A.. monitoring of blood pressure, heart rate and rhythm, heart strength (using echocardiography), coagulation (including platelet numbers), WBC counts and differentials, serum chemistries, urine analysis, strength, bowel sounds, lung and heart sounds, and mentation; B. support appropriate for the patient with sepsis including the administration of broad spectrum antibiotics, antiemetics if the patient is vomiting (using small doses of chlorpromazine following hemodynamic stabilization), and low dose subcutaneous heparin (50-100 units/kg q8hr); C. cardiopulmonary support with ionotropic drugs (dobutamine) and oxygenation, including use of a nasopharyngeal oxygen catheter to deliver up to 50 - 80% inspired oxygen or ventilatory support based on blood gas analysis, chest radiographic findings, and clinical signs of respiratory compromise; D. tender nursing care that involves psychological support for both the pet and the owner, physical therapy (range of motion exercises, turning over frequently, skin and hair care (frequently requiring a closed system urinary catheter system to keep the patient dry), respiratory therapy (stimulation to take deep breaths frequently), and pain control as required (using infusions of opioids such as morphine (0.05 -0.2 mg/kg/hr), fentanyl, oxymorphone, etc.) and or the use of epidural morphine (0.1mg/kg).

All monitoring and treatments must be recorded and charged for properly. A flow chart should be used to record this information in a chronological order as things were done or observed. For further information I recommend reading: Kirby R: Septic Shock in Kirk's Current Veterinary Therapy XII Small Animal Practice, W.B. Saunders, Philadelphia, 1995.

The goals and steps of surgery are seven fold (all are considered key steps):

1. Explore the entire abdomen to find all pathology present and to take appropriate tissues for histopathology examination and culture. Pancreatic biopsies are taken using a ligation method where 4-0 polypropylene is used to "rope" a small wedge of tissue and tightened. The tissue trapped outside the ligature is removed carefully with an 11 blade and placed on a sterile indicator and placed in a small specimen basket and then put into 10% buffered formalin.

2. Debride and remove all necrotic and suppurative tissue that is obvious on examination. Frequently the pancreas will appear white, necrotic, firm and suppurative. Incisions should be made over these areas to open the capsule and a small strabismus scissors is used to resect the necrotic suppurative tissue. Direct irrigation with a syringe filled with warm saline connected to a 21 g needle and suctioning with a Fraiser suction tip will be required for each area of suppuration. In some cases large peripancreatic abscesses and necrotic tissue will be found and require resection and placement of suction drains in the left-over bed. Resection of pancreas is occasionally necessary if its entire thickness is necrotic;

3. Ensure that obstructions of the duodenum and bile duct are not present and if found to correct them. Resection of the duodenum should only be attempted as a last resort. If it is still viable a gastrojejunostomy can be done to relieve the proximal duodenal obstruction. A cholecystojejunostomy with a wide ostomy can be done for complete common bile duct obstruction if the gall bladder is viable;

4. Irrigate the entire abdomen until the effluent is clear and then dry it;

5. Place a 3.5 to 8 French jejunostomy tube for feeding and begin infusion of a clear blue (food coloring added) liquid electrolyte and glucose solution (Resorb, Electramine [Vitae, Inc], Plasmalyte [Baxter] w/5% glucose). An alternative to the placement of a gastrojejunal catheter for feeding. A jejunostomy tube is placed through a gastrostomy tube and then manipulated into the jejunum. A woven wire styleted finer bore tungsten weighted catheter long enough to reach the well into the proximal jejunum is required;

6. Place a gastrostomy tube for decompression or verify proper position of a nasogastric tube placed for decompression, with the tip of the tube in the antrum;

7. placement of drainage and lavage catheters as required or after catheter placement leaving the abdomen open to allow effective drainage. If the pancreatitis had lead to suppurative peritonitis, based on gross examination, the abdomen is left open. Only the caudal 1/3 of the abdomen is closed and all falciform ligament is removed in the process. Omentum is placed around the viable debrided pancreas and suction drains (Sil Med) are placed on both sides of the pancreas before the omentum is wrapped around the area. In most cases where the abdomen is left open are closed on postop day 3-5 and suction drains used; Following the completion of the goals listed above the abdomen is closed (or left open as indicated), a sterile dressing applied and the patient admitted to the ICU for continued supportive care. Placement of a central line should be done if one is not already present. Another consideration is placement of an arterial catheter for continuous monitoring of arterial BP. A nasopharyngeal oxygen, NG, and urinary catheter are also placed before transfer to the ICU.

For patients with severe pancreatitis 24 hour continual ICU care will be required. The systemic inflammatory response is rather severe in these animals. In a recent series of cases reviewed all had jejunostomy feeding tubes. Major organ failure followed DIC in those patients not surviving. Sepsis and pulmonary failure were a common hallmark to impending death in those that did die. Most cases (75%) survived with aggressive ICU care but costs were very high (several thousand dollars were not uncommon). From past experience with similar cases, without all the supportive and surgical care as outlined here, virtually 100 % would have died.

PROTOCOL – MANAGEMENT - SEVERE PANCREATITIS

Assessment with ongoing support - ? Is it going to be surgical?

Support Aimed at preventing further ischemia and any bacterial infection

IV Fluids continuous – ave .3 times maintenance, colloids key

Antibiotics – broad spectrum high doses (amikacin, metronidazole, cefazolin)

NG tube – decompression but also trickle feeding of tri-di peptide died

Hyperbaric oxygen treatments to increase oxygen levels within the pancreas

Analgesia support – low doses of morphine as a CRI or fentanyl or fent patch

Fresh Frozen Plasma - a major determiner of survival with severe ones

Pentoxifyllinel – for endothelial protection from WBCs and adhesions

Consider mild multiple saline enemas to decrease colon of bacteria

Surgery IF support NOT working after several days OR rapid progressive course + DPL

Two IVs best one with CVP, doppler, epidural catheter, NG tube presurgical

Wide xyphoid to pubis and irrigation and debridement and J tube placement

Possibley leave the abdomen open and percolation with oxygen at 3 ml/kg IP

NG tube on continuous aspiration with glucose / glycene feedings.

Physical Therapy to help prevent deep vein thrombosis.

Practical management of severe wounds and open fractures begins with initial assessment and management. The first priority is the control of severe hemorrhage that may be associated with the injury.

Described in order of preference.

1. Direct pressure: Apply direct pressure by hand over a dressing over the entire bleeding area. In the absence of compress, a bare hand or finger is used. A pad of cloth or gauze (compress) held between the hand and the wound helps control the bleeding by absorbing the blood and allowing it to clot. The compress can be bound in place using bandage material which frees the hands of the first-aider for other emergency action. Do not disturb blood clots after they have formed within the compress. If blood soaks throught the entire pad, do not remove the pad, but add additional layers of cloth, and continue to direct hand pressure more evenly.

2. Elevation: Unless there is evidence of a fracture, a severely bleeding open wound of the paw or leg can be elevated above the level of the heart. This elevation uses the force of gravity which helps reduce blood pressure in the injured area, thus slowing down hemorrhage. Elevation is more effective in larger animals with log limbs where greater distances from wound to heart are possible. Direct pressure with compress must also be continued to maximize the use of elevation.

3. Pressure on the supplying artery: If external bleeding continues following the use of direct pressure and elevation, application of digital pressure over the main artery supplying the wound can be very successful. Apply pressure to the femoral artery in the groin for severe bleeding of the rear leg; the brachial artery in the inside of the upper front leg for wounds of the front leg. Always supply direct pressure in addition to the pressure point when it is used.

4. Pressure above and below the bleeding wound: This can also be used in conjunction with direct pressure. Pressure above the wound will help control arterial bleeding (bright red, pulsating blood), pressure below the wound will help control venous bleeding (dark, oozing blood).

5. Tourniquet: Use of a tourniquet is dangerous and should only be reserved for a severe life-threatening hemorrhage in a limb you do not expect to save. A wide (2" or greater) piece of cloth should be used to wrap around the limb twice, and a knot is tied. A short stick or similar object is then tied into the knot as well. Twist the stick to tighten the tourniquet until bleeding stops. Secure the stick in place with another piece of cloth and make a written note of the time that it was applied. After application it should not be loosened until in the OR. A pneumatic blood pressure cuff CAN be used without threat of limb loss for up to 2 hours in some cases this is because of the very wide with and it being full of air.

After the bleeding is controlled the next step is to protect the wound from getting any further contamination and prevent it from becoming dehydrated. This is most commonly done by applying a water or saline soaked dressing onto the wound and a protective bandage applied. Do not remove or disturb the cloth pad or dressing initially placed on the wound as this will cause further dehydration, pain, blood loss and heat. The wound should be "immobilized" using a compressive dressing. Irrigation and cleaning of the wound should follow. Sedation is often required. In severe wounds the addition of a local or regional anesthetic is recommended prior to the irrigation and debridement. An intravenous broad spectrum antibiotic should be give prior to the commencement of the debridement

Open Fracture Management. Splint them where they lie Use spica splints mad of newspaper if you have any doubt that there could be a fracture associated with the wound. These DO NOT cause a point of stress on the fracture. Most fractures do better and the soft tissues certainly survive better and have less microvascular injury. Sedation is generally required. Truetta even used these splints on open fractures with fair results.

Most fractures can wait for surgery until the patient is stable. However this is not the case with open wounds if at all possible and those involving the skull or spinal cord. Definitive surgery is best done as within hours of the injury.

Just like all injuries, the management of penetrating injury follows the same guidelines and priorities as for general trauma care. Treat the most life threatening problems in priority first and then follow up with those that are limb threatening and then those that are non-limb or life threatening. Start by assessing the scene for safety. Make it safe if it is not. Assess for immediate life-threatening conditions and treat them if they are present. Perform a thorough physical exam and obtain a thorough history. Treat the problems found definitively and complete follow-up care. Document all findings, communications, estimates, agreements, actions well.

There are also other important management decisions that must be made that are specific to the penetrating trauma itself. It was stated in the past that every traumatic event that penetrated the skin should undergo operative exploration and repair. However we know today that this old rule (started before the widespread use of broad spectrum antibiotics ) is no longer applicable.

Today a "selective management" concept of handling penetrating wounds is recommended and is based on the following criteria:

1. careful assessment (physical exam, radiographs, ultrasound, lab indices, and monitoring),

2. knowledge of the mechanism of injury, forces involved, and physiologic consequences,

3 knowledge of anatomy involved or possibly involved,

4. past clinical experience with the management of the various types of penetrating injuries,

5. owners financial commitment,

6. facility and staff abilities,

7. other concurrent medical conditions the pet has.

If the animal is now brought to your hospital scan the patient quickly for injury including all surfaces. If external bleeding, a sucking wound in the neck or chest is noted a compressive or triangular occlusive dressing should be applied respectively. Impaled objects should be stabilized with a dressing if applicable. They should not be removed unless 1. they are thought to be interfering with the movement of air in the airway; 2. they are continuing to create lacerating trauma due to continuous movement that can not be controlled; 3. they are endangering the staff (rare).

The wounds should be assessed closely. Clip the area around the wound and note the wound's location, size, shape, the presence of air or subcutaneous emphysema, the amount of separation of the skin from the underlying tissues, surrounding skin color, the presence of crepitus, pain, and deformity. Cover large open wounds with a water soluble jelly and dress them to keep them clean. Place an antibiotic or antiseptic cream over smaller holes and surrounding areas. Its important to form a protective barrier over the penetrated skin as soon as possible to prevent further contamination with bacteria; particularly with "hospital" entrenched microflora and enteric organisms from the patient. Decisions are then made as to the care options available. Options are based on the animal's overall condition, the wound (mechanism of injury, location, severity), finances available, equipment and help available, and past experience.

SPECIFIC MANAGEMENT RECOMMENDATIONS

General Wound Management - Wounds that do not show signs of deeper tissue disruption, hemorrhage or sucking air are able to be treated conservatively initially as previously mentioned. Simple clipping, gentle cleaning, and dressing are all that is required. All should be treated with broad spectrum antibiotics . It is recommended NOT to use Baytril or other quinolones as a first line broad spectrum antibiotic in most cases. They should be reserved for serious infections and not for prophylaxis except when penetration may involve the brain , sinus, or spinal canal. First generation cephalosporins are otherwise recommended. If the wounds are very severe these are best started intravenously (e.g., cephazolin 40 mg/kg the first dose then 20 mg/kg thereafter Q 6 hr.). Begin the antibiotic coverage BEFORE the would is debrided by at least 30 minutes if possible. If the oral cavity, upper airway, or GI intact is involved then metronidazole at 7 mg/kg IV tid is added. Aminoglycosides are reserved for those cases involving significant gastrointestinal contamination. Gentamycin is given at 5 mg/kg IV or IM Sid and coursed for 3-5 days.

Bite Wound Management - Small skin holes caused by teeth with the muscle intact and no separation of the skin from underlying tissues warrants in some cases only cleaning the area and placing the patient on broad spectrum antibiotics. If tissues under the skin are separated from the skin, fat exits the holes , or subcutaneous tissues feels disrupted then exploration is highly warranted. No cases ever should the wound be simply flushed with saline and sutured closed.

The bite wound minimally is left open to drain. Lacerations and avulsion defects are covered with water soluble jelly, the entire area is clipped and scrubbed and formal exploration of the deeper tissues accomplished. If the skin surrounding the wound is separated from underlying tissue the exploratory incision should encompass this entire area unless special methods are utilized to allow for thorough visual exam without complete exposure (involving high intensity fiberoptic headlight or endoscopic equipment). Upon wide exposure all devitalized fat and muscle should be removed. This needs to be aggressively done. If the thoracic, abdominal or other cavities (calvarium, sinus, joint, spinal canal) are penetrated surgical exploration of those cavities, and debridement, repair, and irrigation are done as needed.

Massive gastrointestinal rupture and contamination cases should not have the abdomen closed. All other cavities, following irrigation and drying are closed. Suction drains are placed where dead space is present if the use of compression dressings can not be used effectively. Sil-Med and other silicone multiholed suction drains and collapsible reservoirs are recommended to be used. But home-made multiholed catheters and continuous evacuation systems made from syringes with plungers held out with a pin can also be used. Gravity assisted passive drains are acceptable where they can be covered and not at great risk for significant contamination which may lead to ascending infection. Wounds are closed with minimal monofilament absorbable subcutaneous sutures used to bring the deeper tissues together. Skin closure may include near far far near or vertical mattress patterns that help close the subdermal and subcutaneous layers.

Gunshot Wound Management - All penetrations should be carefully examined to attempt to determine trajectory and the type of missile, and energy imparted to estimate the possible damage caused. In cases were financial constraints are not a problem most all cases should receive radiographs and a planned exploration based on clinical signs and suspicions for deeper injury. Bullets passing through the chest may be handled conservatively in approximately 50% of the cases Those involving hemorrhage are begun with diagnosis centesis, chest tube placement, and continuous suction drainage. Counterpressure of 20 mmHg can be helpful for controlling or slowing bleeding. Blood loss may require transfusion, autotransfusion, and exploration if hemorrhage continues or clinical signs worsen. Bullet injuries involving the abdominal cavity warrant exploration early in the course. Serosal patching of repaired visceral organ injuries is recommended. Wounds involving other tissues are managed as described for bite wounds. Debridement and irrigation are recommended in most cases except for shallow and low velocity bullets. This includes shot from shotgun injury with wide patterns, provided no clinical signs or radiographic evidence of deeper penetration into abdomen, etc. is observed.

Impalement Wound Management - The area and cavity involved are explored before the impaled object is removed. For example an arrow penetrating the chest and abdomen should be left in place until both the chest and abdomen are opened on the midline and removal is done under direct visualization of all the structures involved. If the object is tamponadeing hemorrhage or leakage of gastrointestinal tract contents, occlusion by vascular clamp or Rummel loop should be performed before the object is removed. Management is otherwise similar to bite wounds.

The tenets I subscribe to regarding the emergency management of severe wounds and open fractures can be summarized in 15 statements (Table1). Some of these are old and well proven by their use in many thousands of wounds while others have only come to be realized over the last few years. Some overlap. These are what I believe and are probably not shared by all trauma surgeons but by following them I have had success that I do not think otherwise possible and by teaching them to others I hope others will also realize success in the management of the truly most severe cases in practice.

Table 1-

Tenets of Emergency Management of Wound and Open Fractures

1. The first priority is yourself: Consider all patients with traumatic wounds as having human blood contamination until proven otherwise. Therefore always put on gloves before the patient is touched and use caution. Use Universal Precautions as outlined by OSHA regarding BSI (body substance isolation) precautions (see references).

2. The second priority is providing good assessment of the entire patient and to provide adequate oxygenation, ventilation and circulation and to control major bleeding. The best way to stop bleeding initially is with direct pressure done by hand or with a pneumatic pressure cuff inflated proximal to the wound if possible. Some cases may require immediate surgery to cross-clamp bleeding vessels. Until that time so not let up pressure.

3. Wounds should be kept clean and moist with sterile saline soaked sponges applied from the very beginning of emergency care. Most infections in fresh wounds or surgical wounds come from the hospital environment therefore protect the wound with a temporary sterile towel "bandage" as soon as the patient is seen, even before the patient is placed on an exam table if possible. Wounds covered immediately and kept moist with a saline dressing are associated with significantly less nosicomial infections.

4. Impaled objects should be removed only under controlled surgical conditions with exposure of the deeper tissues involved. The only exceptions are if the object is obstructing the patient’s airway or the object prevents transport and medical care..

5. All wounds involving injury below the skin should be widely clipped, thoroughly explored, debrided as necessary, and lavaged extensively. They should not be closed if they can not be debrided completely clean within 6 hours of the injury or can not be completely removed. Small punctures should be opened and gently irrigated and inspected. They should be left open to ensure drainage Irrigation fluids should not be forced.

6. Debridement of all contaminated and devitalized tissue and copious irrigation are accomplished as soon as possible. If gross contamination is still present following these the wound should never be closed. Rather the wound is packed open with wet saline gauze sponges. This is followed by a dry dressing. Wet-to-dry dressings are changed daily. The wound can generally be closed on day 3-6 when a good granulating tissue bed is present (delayed primary closure) so long as it can be done without much tension.

7. Primary or delayed closure of traumatic wounds following debridement should be completed with non-absorbable monofilament sutures in an interrupted vertical mattress pattern or a near far -far near pattern avoiding the placement of any subcutaneous sutures.

If subcutaneous sutures are used to take the tension off the skin closure layer or ligations are needed to be done use the smallest monofilament absorbable or non absorbable material that is easy to work with such as 3-0 or 4-0 polypropylene.

8. Dead space should be treated with closed suction drains or compression bandages. Sutures placed can not obliterate dead space – only compartmentalize it. Penrose drains should be used in clean wounds only if the exposed end and wound can be covered completely with a sterile compressive dressing.

9. Unstable fractures and luxations should be splinted as soon as possible: "Splint them where they lay". Bubble wrap works well as a light weight Robert Jones Dressing and newspaper can be used effectively for spica splints. Transporting on a flat rigid object like a board can accomplish "emergency splinting" of the entire patient as well as any obvious fracture and is recommended as a first aid procedure as well as intra-hospital .

10. Wounds and fractures are painful and patients always should be treated with analgesics. Local and regional anesthesia, analgesia and sedation should be not be hesitated to be used as needed. Epidural anesthesia and analgesia is a very effective way to manage pain and catheters provide a very good means of managing wound and fracture pain.

11. Open joints and fractures should be thoroughly debrided and irrigated as soon a comfortably possible. With the use of local, regional or epidural anesthesia this can be accomplished within hours of the injury in most cases in even the more unstable cases.

12. Systemic broad spectrum antibiotics do not take the place of good wound debridement and irrigation but are recommended to be started before the debridement is begun and continued a minimum of 48-72 hours.

13. In severe wounds the importance of enteral nutritional support is a key to the prevention of infection that is just as important as good debridement, irrigation, and broad -spectrum antibiotics. This should be started within hours of the injury.

14. Rest and immobilize the wound, fracture or luxation with compressive dressings to prevent postoperative swelling. In open unstable injuries use external fixation devices (pins and clamps) to allow dressing changes and wound care without loosing immobilization is recommended.

15. Ancillary treatment methods that help assure good oxygenation and blood flow to the injured tissues have a place and should be used: These include the oral administration of pentoxifylline helps improved red cell flexibility; physical therapy (massage, passive range of motion exercises, etc.), hyperbaric oxygen treatments, and even the local application of leeches in distal extremity injuries that have much venous congestion.

A case recently presented to our hospital will severe to illustrate many of these tenants:

Louie is a 10 year old Yellow Labrador that was presented to the emergency service after being presumably stuck by a motor vehicle. The owner stated that Louie had been discovered on the side of the road by a passer-by. He was found laying in the snow and had a puddle of blood next to him. He was unable to rise on his real legs. His left rear limb had an easily recognizable severe wound and fracture with much soft tissue injury. The leg was in an abnormal position. The owner placed him on a board and into his truck and immediately brought him to the service. This acted to "splint the entire patient" not only the severely injured limb (Tenet No 9).

Gloves were put on by the emergency team (Tenet No.1) and a sterile towel was applied around the open wound immediately before he was carried on the board into the hospital (Tenet No 3) Assuming significant injury and shock flow – by oxygen was delivered to his face while assessment was being performed. A team member was also preparing to place an intravenous catheter, pull blood for lab analysis, and begin Plasmalyte at a moderate rate. As this was accomplished a thorough assessment protocol was begun to be carried out (Tenet No. 2):

A primary survey or evaluation was done and revealed the following:

LOC (level of consciousness) = alert but quite

Airway = patent

Breathing = normal breathing pattern and rate, breaths sounds heard bilaterally

Cardiovascular = membrane color pink, pulses slightly fast but easily palpable,

Capillary refill time 2 sec, Jugular vein filling time 4 seconds with volume slight,

Heart tones adequate and no murmurs or gallop or arrhythmia, rate same as pulse

Disability = sensation present in all four extremities on toe pinch

Everything else on a quick visual assessment = no obvious external bleeding

Vitals Signs recorded:

HR 140, RR 30, BP 120/80, rectal temp 100, weight estimated to be approx. 40-45 Kg.

Secondary survey or evaluation revealed normal findings until the caudal one-half of he body was reached. There where numerous superficial abrasions noted on the caudal abdominal skin in the inguinal region. The left rear limb had a large degloving injury and open fracture luxation at the distal end of the tibia and there was much displacement. There was a large area wound involving the medial aspect of the left thigh. The nail bed of the foot was squeezed and sensation of the pinch was acknowledges by the dog. The foot was obviously swollen but some pink color was present in each of the nail beds. There was obvious contamination with road debris throughout the wound. Bowel sounds were not heard on auscultation. There was no pain or distension of the abdomen. There was a small amount of blood at the tip of the prepuce. The urethral meatus was the source of the hemorrhage. Rectal exam was unremarkable. Pain was elicited when the right hip was manipulated. The owner was asked about any possible allergies, when the dog was last fed, any past history of illness or surgery, on any medications and answers recorded.

For the sake of brevity only the most pertinent aspects of care as outlined in the tenants listed above will be described from here on.

Emergency care of the wound-fracture consisted of the following:

The wounds were initially covered with saline soaked sponges (Tenet No.3) while intravenous enrofloxacin (10 mg /kg), metronidazole (7 mg/kg) and cefazolin (40 mg/kg) was administered (Tenet No.12 ). Sedation (hydromorphone 0.15 mg/kg and acepromazine 0.001 mg/kg) was provided intravenously following continued fluid support and the wounds were wrapped with more sterile towels and "trauma radiographs" (lateral films of the neck, chest, abdomen, pelvic region) were taken. This revealed a severely displaced fracture luxation of the left tibial-tarsal joint (and a right coxofemoral craniodorsal luxation . The wounds were then initially irrigated and debrided of all gross contamination easily visible (Tenet 6). The wounds were dressed with wet saline dressings and no attempt at closure was done (Tenet 5). Bubble wrap was used over a dry dressing of 4x4 gauze and brown cling to make a light weight Robert Jones dressing that would provide some stability to the fracture luxation ( Tenet 9) Analgesia was provided as needed with intravenous hydromorphone and a 100 mcg fentanyl patch was applied to the right distal extremity. (Tenet 10 and 11). A urinary catheter was placed and gross hematuria was noted. Continued monitoring in the ICU was done and 400 mg of pentoxifylline begun orally bid as well as twice a day hyperbaric oxygen treatments. He initially received 100 % oxygen at 15 phi for an hour each treatment in a stainless steel chamber (Companion Animal Hyperbarics, Inc.,) and then 40% oxygen at 4.4 psi for an hour each treatment. This was done using a collapsible and portable hyperbaric chamber (Animal Hyperbarics, Inc.). (Tenet 15). More definitive wound care and surgery was performed the following day.

Under general anesthesia (ketamine, diazepam, isoflurane, hydromorphone, glycopyrolate) and continuous positive pressure ventilatory support with a mechanical ventilator) an epidural catheter was placed to provide epidural anesthesia with lidocaine, bupivicaine, hydromorphone. Louie was taken to surgery after clipping and preparation of the limbs (Tenet 11). The coxofemoral luxation was repaired by open reduction and internal fixation as attempts at closed reduction had failed. The left rear limb was then suspended and surgical preparation completed using chloroxylenol 3% (Technicare). The wound was debrided and irrigated. A fiberoptic surgical head-light was used to increase illumination which facilitated the cleaning and debridement process. Replacement of the medial collateral ligament was completed with three screws, washers, and No. 5 Ethibond (a braided polyester fiber suture) to simulate the long and short collateral ligaments (Aron, Purinton 1985). A type 2 external fixator was applied for stabilization of the entire joint (Tenet 14).(Clark 1997). Penrose drains were inserted through the posterior aspect of the wound to increase drainage ability where a pocket between skin deep fascia has formed (Tenet 8) and saline dressings applied for wound coverage. Two leeches were applied to the toes to assist with venous congestion and to help prevent microvascular thormbosis and a sterile dressing applied. During the entire 6 hours of surgery for adequate analgesia and anesthesia the isoflurane inhalational concentration required was able to be maintained below 0.5-0.7 % due to the use of the epidural catheter. Postoperative radiographs were completed which revealed the implanted screws and washers and the reduced luxation of the tibial-talar joint and the reduced coxofemoral joint with the two screws used to anchor the supporting Ethibond suture. (Tomlinson 1997) During and immediately after surgery hematocrit, total plasma protein, blood glucose, and venous blood gases were monitored. At the conclusion of the surgery because of the drop of hematocrit below 20 % and a total plasma protein below 4.5 g/dl a unit (500 ml) of stored whole blood was administered.

The patient was admitted back to the intensive care unit with monitoring of ECG, BP, vital signs, urine output and receiving nasal-pharyngeal oxygen. The only new complication noted in the immediate post operative period was the development of paroxsymal unifocal ventricular tachycardia that resolved with 36 hours following surgery. The previously noted hematuria gradually cleared up spontaneously over a period f a few days. Louie remained comfortable and received enteral nutritional support \(Tenet 14) and analgesia via his epidural catheter and fentanyl patch (Tenet 10). Physical therapy (Tenet 15) and tender loving nursing care in the ICU and daily dressing changes (Tenet 6) were performed. Approximately 5 medical grade leeches (LEECHES USA) were applied to his foot daily to decrease edema and help maintain microcirculation in the distal extremity. The injury had essentially caused a 360 degree degloving injury with 270 degrees being an anatomic degloving with loss of all the skin and subcutaneous tissues. The caudal portion of the limb had a complete physiologic degloving as the skin and subcutaneous tissues had pulled away completely from the deeper structures. Because of this the lymphatic draining the toes were literally destroyed and the consequence was significant edema formation. The leeches significantly helped with the reduction of the edema until full thickness grafting was able to be accomplished.

Ten days following the injury Louie underwent a full-thickness mesh grafting with skin taken from his left flank. The graft was applied to the lateral aspect of the hock. Petroleum impregnated gauze was applied following Bacitracin ointment application. This was followed by a sterile layer of 4x4 gauze pads and then cast padding and cling gauze. Seed graphs were applied to the medial side of the wound at various stages following the full-thickness grafting. Dressings were continued to be changed every two to three days as needed. The KE apparatus remained in place for one month after its application to provide support for the skin wound that were healing One week following the removal of the KE apparatus the wounds were almost completely closed with only small areas between the seed grafts were still open. Due to deep crusty snow his owner was using a boot to protect the graft sites. Louie was using his leg quite well and his owner was quite pleased.

This case illustrates many of the multiple tenets I have come to follow that are involved with the emergency care and management of serious wounds and open fractures. It also provides insight to the use of hyperbaric oxygen and leeches for the treatment of microvascular compromised tissues.

CARDIAC ARREST PREVENTION AND MANAGEMENT:

Much has changed in our knowledge and techniques regarding resuscitative management of the cardiopulmonary arrest (CPA) patient (canine or feline) since the protocol on cardiopulmonary resuscitation (CPR) was published by the American Animal Hospital Association in 1981. These changes are based on experimental studies performed and published within the last 10 years that have revealed the true mechanisms by which closed chest CPR generates blood flow to the brain and how clinicians can utilize them for more effective resuscitation. It is also based on experimental and clinical investigations involving CPA management the author experienced when at the University of Georgia from 1980 to 1991. During this time, new concepts and techniques were adapted and significant increases in resuscitation and survival with preserved neurologic function resulted. Now even the title of the resuscitative effort has changed from CPR to CPCR or cerebral and cardiopulmonary resuscitation

This section will discuss expectations, practical readiness suggestions, the mechanics of blood flow generation during closed and open chest CPCR, and ways that it can be enhanced. Based on this information, current recommendations for CPR will be made.

The reason for every veterinary practitioner and nurse to keep current on new techniques and information about CPR is that when it is used, increased survival results. At the UGAVTH from 1980-1982 there was an average of 4 in-hospital CPA events being attempted to be reversed per month. Survival with good neurologic function return was less than 0.5%. With the gradual introduction of more careful monitoring, believed to have lead to an earlier recognition of the CPA event; the use of more effective techniques for the generation of brain and heart blood flow with better methods of monitoring this effectiveness; and improved post resuscitation care, survival with good neurologic function increased from this less than 0.5%, to over 5% in 1990.

1.The use of Doppler monitoring for monitoring of most anesthetized patients, in addition to ECG and esophageal stethoscope for cardiopulmonary monitoring;

2.Improved readiness, in terms of equipment, drugs and manpower;

3.Doppler monitoring of cerebral blood flow via the ophthalmic vessels during CPR.

4.The use of interposed abdominal counterpulsation during both closed and open chest CPR.

5.The use of high dose epinephrine very early in all forms of CPA.

6.The use of intratracheal atropine and epinephrine early in CPR.

7.Improved respiratory support and monitoring post resuscitation.

8.The addition of neuroprotective drugs to the protocol in the immediate post resuscitative period (prednisolone sodium succinate, mannitol, desferoxamine, and in some cases dimethyl sulfoxide).

With the addition of the above management techniques, without any changes in patient selection criteria, i.e., all animals suffering a CPA the were not considered "terminal", success at resuscitation in the generation of spontaneous heart function and adequate pulse pressures jumped to 50%. Successful neurologic resuscitation (resulting in good neurologic function) jumped to nearly 20% of those in which treatment was continued.

Although survival from CPA can be as high as 20%, most of the time historically in most settings only a few percentage of animals will be discharged because of time delays and, in the author's opinion, too much reliance on techniques that are not effective, e.g., closed chest CPR in large dogs. Therefore anytime an arrest occurs a very guarded prognosis is in order. Actual survival figures that each veterinarian can expect in their practice however will not only be influenced on how effective brain blood flow can be generated but also on such variables as the following:

1.The condition of the patient (diseases present) prior to the arrest and number and severity of the physiological derangements present at the time of the arrest;

2.The length of ischemic brain and heart time, i.e., lag time prior to effective resuscitation;

3.Cause or causes of the arrest itself;

4.Whether the CPA event is really a "true arrest" electrically documented or "just" a very low flow state, as indicated by lack of palpable pulses;

5.The type of ECG arrest arrhythmia present;

6.The post resuscitation care performed;

7.The amount of time and money the owner was willing to commit to the care of the animal. This is one of the most important.

Proven and expected increased survival rates, when using techniques that generate effective brain blood, should stimulate every veterinarian and nurse to want to learn them and become proficient at them. From the outset it should be emphasized that in order for proficiency to be attained everyone must learn the skills through actual hands-on practice sessions, not just from reading how. Ways to attain mastery at these skills can be learned using psychomotor training tools such as the CPR DOG (Nasco Co, Fort Atkinson, WI), PET-A-KIN (Animal Health Foundation, Philadelphia), or from working with fresh cadavers.

Every practice should have at least one designated area where CPR is performed.

The anesthesia induction area and the surgery theater are the two areas suggested. A crash cart, with appropriate drugs and equipment should be made and organized so that things can be found easily. Using foam rubber to line the cart and sections cut out where each piece (tube. drug, syringe, etc.) is placed, with clear labeling, is recommended. Attaching a syringe to each ET tube for inflation of the cuff and the attachment of tape or gauze ties to secure the tube is also recommended. It is important to have a selection of various size tubes arranged for easy access.

Key pieces of equipment required include a Doppler blood flow detector and pediatric flat flow probe (Parks Medical Electronics), an ECG scope and paper recorded, a laryngoscope, source of fresh oxygen that flow at levels at lease 15L/min, and an bag-valve (Ambu bag), much preferred over the use of an anesthetic machine to provide the positive pressure ventilation required, and a DC defibrillator with paddles.

Key drugs required include only epinephrine (or other alpha adrenergic drug), atropine, lidocaine, and prednisolone or methylprednisolone sodium succinate. Less important drugs (sodium bicarbonate, calcium chloride or gluconate) and neuroprotective drugs (mannitol, desferoxamine, and dimethyl sulfoxide) are also recommended. Vials or ampoules of these drugs are placed in sections cut out in the foam rubber, and syringes with 18g needles attached placed next to each drug.

The basic (ABCs of CPR) and advanced (drugs and defibrillation) cardiac life-support protocols should be reviewed and practiced as a team whenever time permits if CPR is not performed regularly. The team should be made up of all employees in the practice that can mustered a anytime. The ideal number of people involved is 4. Their job descriptions include:

Rescue Person No. 1. Team Captain; most experienced, a doctor, calls the shots (drug administration, etc.), assesses effectiveness, keeps track of time, records results. Often is person No.3 as well, at least initially. Will perform cutdown, thoracotomy, defibrillation, etc. Will begin the open chest CPR after the thoracotomy is done. Others can continue the direct massage. Closes the thorax after the heart is stable 20 minutes (with a chest tube in place) * Could allow some one other than himself or herself to do tasks (another veterinarian) which would allow him or her to play a better captain role with the ability to observe and coach the team through the "code".

Rescue Person No. 2. Ventilator; using an AMBU bag, gives ventilation after airway is secured (most frequently done by the team captain but could be Person 2).

Rescue Person No. 3. Chest compressor or heart massager. Often is person No.1 initially.

Rescue Person No.4. Secures monitoring electrodes for ECG, Doppler probe for blood flow monitoring; Administers drugs, charges defibrillator.

There are three mechanisms involved with the generation of brain blood flow in the animal receiving either closed-chest CPR (CCCPR) or open-chest CPR (OCCPR). It is the generation of adequate forward oxygenated blood flow to the brain and heart that is the ultimate goal in CPR. Safar and others have emphasized the importance of brain blood flow over cardiac blood flow in resuscitation, calling resuscitation CPCR (cardiopulmonary cerebral resuscitation) rather than simply CPR. The brain requires 2 times more blood flow per gram of tissue (100ml/gram/min) compared to the heart to sustain cellular survival.

The mechanisms are the following:

Thoracic (pulmonary) pump - where blood flow is generated by the squeezing of the pulmonary vasculature by chest compressions with CCCPR and by airway pressure influences with both CCCPR and OPCCPR. In CCCPR increased intrathoracic pressure, generated by compression of the chest also influence venous pressures and flows. It causes an increase in venous pressure which decreases cerebral perfusion pressure and flow. This mechanism is then not nearly as efficient in the generation of forward blood flow with CCCPR as the cardiac pump in OCCPR because of this influence on venous pressures. The thoracic pump is the most important mechanism in CCCPR in dogs over 20 Kg body weight. This is also the mechanism by which "cough CPR" in humans works and which has influenced many changes in the protocol of how to perform CCCPR in all animals over 20 Kg in size (see below).

Cardiac pump - where blood flow is generated by the squeezing of the heart chambers either indirectly as with CCCPR or directly as with OCCPR. This mechanism is more effective in the generation of effective blood flow to the brain because less venous pressure is generated. This is particularly true with OCCPR. In CCCPR in animals over 20 Kg it generally plays only a minor role in the generation of blood flow, whereas it plays the major role in OCCPR.

Abdominal pump - where blood flow in the caudal vena cava is enhanced by placing pressure on the abdomen between chest or heart compressions. This increases cardiac filling during CPR diastole, thus enhancing forward blood flow. It also enhances coronary artery blood flow because it increases aortic diastolic pressure (and indirectly coronary artery pressure).

(1) Recognition that open-chest CPR is much more effective than closed-chest CPR in the dog; (2) When closed-chest CPR is used, it is based more on the mechanism of the thoracic pump rather than on the cardiac pump (discussed previously and more later); (3) Higher doses of epinephrine markedly increase brain and coronary blood flow during CPR; (4) Calcium, in the form of gluconate or chloride, has been associated with poorer resuscitation rates, is not effective in electromechanical dissociation as once thought, and has been identified as playing a key roll in the genesis of reperfusion injury in the heart and brain. Therefore, calcium been removed from the CPR protocol except when the CPA is associated with the use of calcium channel blockers including isoflurane and halothane or in the face of hypocalcemia or hyperkalemia;

The use of abdominal counterpulsation in CCCPR and OCCPR and brief aortic cross-clamping in open-chest CPR substantially increases brain and heart blood flow. Open-chest CPR with aortic cross-camping is the most effective means of providing brain and heart blood flow in the patient with a nonbeating heart; approaching 95% of that observed in the unstressed beating heart.

Definition and Patient Selection

Cardiopulmonary arrest (CPA) may be defined as a sudden cessation of functional ventilation and effective circulation. While CPA is the terminal event in all hopelessly ill patients, resuscitation efforts should not be attempted in these individuals. Resuscitation should, however, be attempted in patients that are or were not expected to die and in which the life-threatening process responsible for the CPA is believed potentially reversible. In cases where doubt exists it should be remembered that "the only alternative to CPR is death" and resuscitation should be performed. The greater the possibility of reversing the life-threatening process, and the earlier the CPA is recognized and treated, the better the chance of successful resuscitation. CPCR as mentioned earlier is cerebral(brain) and cardiopulmonary (heart-lung) resuscitation which is that effort used to try and reverse clinical death that has ensued.

In the past it was stated that irreversible brain death would occur after 4 minutes, however, with the use of cytoprotective drugs, as mentioned before, or in cases of hypothermia, resuscitation has even been successful after one-half hour of full arrest in dogs. Although cytoprotective drugs are still under investigation the few mentioned are now used as additions to CPR protocols once the heart has been restarted and blood flow to the brain appears sufficient and stable. These include mannitol, a hydroxyl radical scavenger at a 0.25 - 1g/kg dose, given twice 4 hours apart or used as a continuous infusion as a 10% solution to provide 4.4 g/kg in 8 hours; DMSO (dimethylsulfoxide) also a hydroxyl radical scavenger, at a 250 mg/kg dose given very slowly over 15 minutes in normal saline and repeated also again in 4 hours; Desferyl (desferoxamine), an intracellular iron chelator which decreases the amount of oxygen radicals formed, at a dose of 40 mg/kg given slowly over 15 minutes in normal saline. All of these drugs are given intravenously.

Prevention of Arrest Certainly Recommended over Treatment

Obviously, if CPA can be prevented this is certainly preferred as resuscitation rate with normal neurologic function returning is still pitifully low (5-10% in most studies, and a maximum of 25% in "ideal" circumstances). Of all of the causes of CPA the most common in our experience at UGAVTH, and those of others, has been hypoventilation and progressive hypoxemia and hypercarbia.

Another cause in seriously ill patients is "silent" aspiration which, in the face of mild to moderated acidosis and hypoxemia, can cause a severe vagal induced bradyarrhythmia that often leads to CPA. Prevention of CPA by both of these common causes in the critical patient requires careful attention to airway and pulmonary support.

Endotracheal intubation and effective positive pressure ventilation are the two modalities that will effectively guard against progressive cardiopulmonary failure and death. With proper training and the use of a laryngoscope all animals, from the smallest cat to the largest obese Bulldog, all tracheas are easily intubated. Since almost all general anesthetic agents, when used, depress respiration, it is also important to provide positive pressure ventilation. Even in the healthy patient airway and pulmonary support are the most important means of preventing CPA whenever general anesthesia is instituted.

With CPA in awake patients, there is a loss of consciousness usually within 10-15 seconds. In anesthetized or unconscious patients a decrease in blood pressure is the most common premonitory sign seen prior to CPA. A few breaths or gasping may occur for a few seconds after cardiac arrest in both awake and anesthetized animals. Pupils dilate and become fixed within 30-45 seconds.

Capillary refill time, as measured by digital compression, may be normal or decreased, depending on the cause of the arrest at the onset. If vasomotor tone and vascular volume are normal at the time of the CPA, capillary refill time (CRT) may continue to be normal (1-1.5 seconds) until vasomotor tone loss, secondary to local hypoxia, occurs. In experimental dogs whose hearts are electrically fibrillated, CRT often continues to appear normal for 3-4 minutes following the onset of CPA.

Absence of a palpable pulse in an accessible artery occurs at the onset and is the specific clinical sign of cardiac arrest. However, no palpable pulse may occur in animals with a very feeble cardiac output and blood flow due to severe hypovolemia (absolute or relative), even though they continue to have spontaneous cardiac function without the presence of an actual cardiac arrest. Similarly, a lack of precordial palpation and auscultation of heart movement and sounds respectively may also occur in severe hypovolemia and hypotension without the presence of an actual cardiac arrest. However, one should assume CPA and treat accordingly if these signs are evident.

It is in these severely hypotensive but not actually "arrested" animals in which often the early treatment of airway intubation, good positive pressure ventilation and closed chest CPR is effective in restoring perfusion.

Although electrocardiographic monitoring and the use of "Beep" boxes that detect each R wave have been very useful for patient monitoring, it should be remembered that these detect only electrical activity of the heart. One form of CPA arrhythmia that is unrecognizable by these means is electromechanical dissociation (EMD). With EMD the electrocardiogram tracing can appear essentially normal despite the fact that there is no detectable mechanical activity of the heart.3 Recent evidence suggests this is due to the influx of ionized calcium into the cell and an acute disturbance in ATP driven coupling and uncoupling of actin-myosin units within the myocardium. EMD has been reported in man to occur most often in septic shock and following electrical defibrillation. However, in our clinical experience, it is a very common arrest arrhythmia in dogs seen in conjunction with anesthetic complications and all forms of shock.

Recognition of severe arterial hypotension that precedes and then accompanies CPA can be accomplished most accurately with the use of Doppler, oscillometric, or direct arterial pressure monitoring devices. Because they are useful in detecting the premonitory sign of hypotension before the arrest they are highly recommended for the routine monitoring of critically ill patients. They are also very useful in general anesthesia monitoring.

The Doppler Blood Flow Detector - Model 811-AL (Parks Medical Electronics Inc., 19460 S.W. Shaw, Aloha, Oregon 97007, 1-800-547-6427, Also available through Eickemeyer Instruments in Tuttlingen, Germany) is the one I recommend (demonstrated at the lecture). It is also the instrument I recommend for establishing whether the treatment of CPA is effective.

The pediatric Doppler flow probe purchased with the detector is connected to the blood flow detector, is placed either on the eye, over the lingual artery, palmar arterial arch, carotid artery or brachial artery. Every time the chest or heart is compressed during CCCPR or OCCPR, respectively, blood flow should be detected with the detector. A swishing sound should be heard, over the amplifier when blood flow occurs in any of these areas and the intensity of the sound is proportional to the velocity of the flow. Every time the chest is compressed or the heart is squeezed a good flow should be generated and that flow detected by the Doppler. If no or a weak sound is generated changes in resuscitation should be made so that the sound (blood flow) is improved.

Direct arterial monitoring is even more preferred over Doppler flow detection because diastolic pressure can be monitored accurately, however, it is often not able to be done at the time of CPR for logistic reasons. It is known that coronary perfusion pressure (diastolic pressure minus right atrial pressure) of at least 20 mmHg is necessary for myocardial perfusion and has been a very good prognostic indicator in experimental CPR studies in dogs,16-18 ideally a diastolic pressure of 40 mmHg (required to perfuse the coronary vessels adequately) should be sought for.

All CPA management begins with the basic ABC's, termed Basic Cardiac Life Support (BCLS). This should be instituted as quickly as possible and in this order: A and B) Ensure a patient airway by tracheal intubation BUT do not complete this intubation until AFTER several breaths are given with a bag-valve –mask after extending the head and neck and closing the mouth on the tongue so the incisor teeth grip the tongue and preventing the tongue from falling back into the pharynx and occluding the airway. Extend the head and neck and give gentle breaths but with enough force to see chest inflation;

Use 100 % oxygen if possible and use a Bag Valve system with a reservoir to get the per cent of oxygen as high as possible (90-100%) verses only 40% if there is no reservoir attached. If an infant bag is used run the oxygen at 4-5 L/M, if a pediatric size bag is used run the oxygen at 6-10 L/M, and if adult size then 11-15 L/M.

Intubate AFTER the BVM or MN ventilations are given for at least a few breaths to help decrease the chance for a vasovagal induced crisis. Some patients have a heart that is still beating but can not be detected and will stop with the vagal and sympathetic stimulation caused by an attempted intubation in a hypoxemic and acidemic patient. Use of a laryngoscope will allow intubation without as much laryngeal and vagal stimulation. IT will also allow intubation to be accomplished without having to lift the head and neck which also stimulates the vagus nerve and also decreases blood flow to the brain. Keeping the patient laterally recumbent or placing them into a dorsal recumbent position will also help prevent aspiration

C) Check pulse and if none compress the chest rhythmically 80-120 times per minute. Breathing should be done every 15 to 30 chest compressions. (30 are NEW AHA GUIDELINES but I question their recommendation use in animals that have had a ventilatory cause of the arrest.

As mentioned prior, due to the finding that the thoracic pump is more important in most CCCPR attempts, increasing the changes in intrathoracic pressure with each compression is the goal of CCCPR.3 The American Heart Association has recently recognized that changes in basic CPR could be made to increase the effectiveness of resuscitation with chest compressions.8 Some changes recommended now are based on published research findings in dogs as follows:

1. Ventilate first to make sure the lungs are expanded well.Take a full 10 seconds to assess

2. Ventilate by mouth/nose rescue breathing or by mask first then intubate.

3. Compress the chest in a "cough like manner" to increase and decrease intrathoracic pressure rapidly

4. Compress the chest at least 80 times per minute making sure no pressure remains on the chest wall during the diastolic component of the resuscitation cycle.

5. Similarly, do not ventilate, or have any residual positive pressure in the lungs between compressions as this impairs venous return to the thoracic cavity.

6. Between chest compressions have all pressure off the chest, compress the abdomen in a manner similar to how the chest is compressed. This "abdominal pump" has been shown to increase oxygen delivery, coronary blood flow and cerebral blood flow significantly in both dogs, swine, and humans. In most studies this is referred to as abdominal counterpulsation.

After the basic life support methods are well underway and extra help arrives, Advanced Cardiac Life Support (ACLS) techniques can be started. Ideally, at least 4 people should be present to perform ACLS. Often before many drugs or cardioversion can be performed effectively "drill sessions" with staff are required! Important advanced cardiac-life support methods to increase the effectiveness of resuscitation should be used if not already instituted. These include the following:

1. Use a strong alpha-agonist [epinephrine] to increase arterial wall stiffness and to increase total peripheral resistance. This allows better intrathoracic arterial flow due to increased resistance of the walls to collapse from the pressure induced during the systolic phases of resuscitation,2 and helps also to increase diastolic pressure (so important in resuscitation of the heart per se as this is the pressure required to insure adequate coronary blood flow). High dose epinephrine of 0.2 mg/kg as an IV bolus followed by the same dose placed in the IV fluid bottle and then given as a slow continuous infusion is recommended. Another dose given down the endotracheal tube is also recommended in hearts not responding well. Transtracheal or intralingual epinephrine given at 0.2-0.4 mg/kg has also been found effective both experimentally and clinically and is also recommended when an IV access is not immediately available. In both these routes the drug should be diluted with saline in a 1:1 ratio by volume. This increases its rapidity of uptake. If the trachea is used the drug is also best delivered as a bolus through a small catheter placed inside the tracheal tube with its tip lying at the bronchial bifurcation. In an unpublished research study I found evidence of epinephrine uptake in arrested dogs within 15 seconds when the drug was given with a small catheter with the tip placed at the carina, where as it took > 1 minute in animals in which the drug was just injected by syringe into the endotracheal tube and followed by ventilation.

2. In closed-chest CPR use a counterpressure device on the pelvic limbs and pelvic area to increase vascular resistance, and "make the vascular tank smaller" therefore requiring less percussive volume (it also helps direct blood flow to the cranial half of the body). This is useful if abdominal counterpulsation cannot be performed. If the chest is open the rescuer should cross-clamp the descending aorta just caudal to the base of the heart. This can be done by using a feeding tube or umbilical tape passed around the aorta and a hemostat used to hold the loop around the aorta tight. Our research has shown that this technique substantially increases brain and heart blood flow. The cross-clamping should be limited to < 10 minutes.

3. If rapid volume support is required for patients that have actual volume losses, e.g. traumatic or hypovolemic shock, it is best done with colloid replacement (6% Dextran or Hetastarch with electrolytes) rather than with crystalloids, e.g., Ringer's lactate, alone. As crystalloids do not stay in the circulation long (< 1 hr) and may then contribute to severe brain edema following the arrest. Fluid expansion is not recommended unless hypovolemia is known to have been present before the arrest.

4. Use 100% 02 to ventilate and combat the ventilation-perfusion mismatching, shunting and overt pulmonary edema which are common, in CPA resuscitation. Ventilation may be also increased to occur with every compression, if necessary. Sodium bicarbonate is generally not necessary unless a metabolic acidosis was present before the arrest or the CPR is extending beyond 10-20 minutes. It is definitely not given in those animals not being ventilated well. Both venous and arterial blood gas analysis is recommended to accurately determine if or how much bicarbonate is required. In most cases of CPR hyperventilation alone is enough to circumvent the acidosis that occurs during CPR.

5. Use rapid-acting corticosteroids which, at relatively high-doses, (dexamethasone, 2 mg/kg) have been associated with significantly higher resuscitation rates. It is believed the corticosteroids enable the "release" of bound ATP in the mitochondria of ischemic myocardial cells and allows membrane function to return. Their successful use in patients in pulseless idioventricular rhythm has been documented.

6. According to guidelines published recently by the American Heart Association and numerous authors in the veterinary literature, all drugs are best given through a central intravenous catheter. Rapid cutdown of the jugular vein and the insertion of a red rubber catheter is recommended when volume restitution is required. However an alternative route for small volume administration of atropine, epinephrine (already mentioned), and lidocaine in patients without central venous access is intratracheally. These drugs have been shown to be rapidly absorbed into the central circulation particularly when injected deep into the tracheobronchial tree through a catheter inserted via the tracheal tube. I personally have seen dramatic results when doubling the intravenous dose, diluting with 5-10 ml of saline or sterile water (required to provide enough volume), instilling down the endotracheal tube, and immediately continuing positive pressure ventilation. A third alternative recommended is to administer the required emergency drugs by a peripheral venous route.

Research in dogs during open-chest CPR has shown that peripheral venous administration is superior to intracardiac administration, but inferior to central venous administration when comparing blood levels achieved at the aortic root. Always make sure the small doses are followed by a bolus dose of saline *(2-20 ml suggested depending on the site and the size of the animal).

7. It is recommended not to give drugs intracardially, because they have been shown to be much less effective by this route, and CPR has to be temporarily stopped. Major coronary vessels also can be lacerated leading to infarction and/or pericardial tamponade. If epinephrine is also deposited within the myocardium resistant fibrillation may occur. One exception to the recommendation against intracardiac injections is when the chest and pericardium are already open (i.e., after a thoracotomy or after a transdiaphragmatic approach to perform open-chest CPR following an arrest during cranial abdominal surgery).

8. Immediately following the left ventricular injection a finger is placed through the transverse pericardial sinus and the ascending aorta is occluded. With 5 to 6 squeezes of the heart the injected drug is "forced" into the coronary circulation, which has been found to be effective where other routes, including central venous or regular intracardiac have not.

9. Two other routes of administration for emergency drugs during CPR which provide a rapid uptake into the central circulation (within 1 minute) are recommended as alternatives to intravenous or intratracheal administration. These are the intralingual (IL) and intraosseous (I0) routes. With the IL route, drugs limited to moderately small amounts (1-15 ml) are injected just under the dorsal mucosal surface of the tongue. The abundant submucosal plexus of vessels contains many arteriovenous connections which remain patent and functioning during CPR. Thus they provide an effective and simple alternative means of drug administration and rapid uptake. With the I0 route, drugs and shock treatment volumes of blood and/or fluids can be injected into a medullary canal and rapid uptake is provided by the abundant endosteum-medullary blood supply.

The I0 route requires the placement of an intramedullary cannula which is rapidly inserted into either the femur (through the Greater Trochantic, Fossa), humerus (through the Greater Tubercle), wing of the ilium or tibial crest.

10. Opening the thorax and pericardium to allow for direct cardiac massage is indicated if external thoracic compressions are ineffective in producing a palpable femoral or carotid pulse or audible Doppler detected blood flow (as discussed earlier) after one to two minutes of closed chest attempts, maximum. This is usually required in animals where significant intrathoracic pressure differentials can not be produced. Examples include, pneumothorax, hydrothorax, flail chest, severe obesity, diaphragmatic hernia, and in dogs simply too large to compress the thoracic wall effectively, [those over 20 kg in many people's hands would qualify].

11. Research in dogs has shown CPR using external chest compressions to be only 20-30% as effective in producing an acceptable carotid blood flow compared to direct cardiac massage. At best, a cardiac index of 1/3 the resting control (before arrest) values was achieved in dogs over 20 kg in weight receiving external CPR, while those receiving direct cardiac compressions achieved a cardiac index of 70% of the resting control (before arrest) value.

Adequate post-resuscitative neurological care is vitally important. Neurologic oriented life support begins immediately after the restoration of circulation and is aimed at those processes seen after CPR that are known to exacerbate neuronal dysfunction. These processes include CNS edema, hypoperfusion, hypertension, hyperventilation, and membrane instability. Key categories of treatment aimed at preventing or lessening these processes include:

1.Ventilatory support (hyperventilation for those not regaining immediate consciousness).

2.Blood pressure support (maintaining diastolic > 60 mm Hg with vasopressors).

3.Volume support (maximizing preload without producing pulmonary edema).

4.Supplemental O2 (if conscious, 40% by nasal catheter usually for 24 hrs)

5.Acid-base rebalance (providing sodium bicarbonate only as required for persistent metabolic acidosis as determined by blood gas analysis).

6.Metabolic support (providing nutritional support, water and electrolytes as needed until the animal can eat). In one patient I had, this was required and was done by pharyngostomy tube for 3 months. The dog made a gradual, acceptable (almost complete) neurologic recovery after being unconscious for almost a week post injury and resuscitation.

7. CNS antiedema and neuroprotective management, e.g., oxygen free radical scavengers like dimethylsulfoxide, barbiturates, mannitol, corticosteroids and calcium channel blockers like lidoflazine. Some of these are new and controversial, but further study of these important aspects of post-arrest resuscitation is highly recommended.