What is the initial challenge in an acute abdomen/colic horse patient?
determine if the case will respond to medical tx or needs surgery
How many acute abdomen/colic cases will respond medically?
What are some reasons that a colic horse that DOESNT respond to medical management wouldnt end up going to surgery?
- -horse not worth it- money or emotionally
- -surgery is not guaranteed to work
- -sx facility too far away
- -case is too severe for too long (poor prognosis)
What would the HR, CRT and MM color look like on a colic horse that tell me he needs to go to surgery?
- HR >80bpm
- CRT >3 sec
- MM = congested or blue
I have a colic horse that has pain I cant control with any pain meds I give it- is this a medical or a surgical candidate?
surgical if pain is difficult to control
What would an abdominocentesis show on a colic horse that needs to go to surgery?
- blood can indicate compromise bowel- sx ASAP
What do I feel on a rectal exam of a colic horse that is a surgical candidate?
distended small bowel and markedly enlarged large bowel
What is the single test I can use to determine if a colic horse needs abdominal surgery?
There is NO SINGLE TEST
I have a colic horse and im not sure if its a surgical candidate, should I send it to surgery now? or can i wait and see?
Send to sx now! even if you havent proven what it is- its better to not lose time
What are the 3 approaches for surgical exploration of the abdomen?
- 1. ventral midline
- 2. paramedian
- 3. flank
If there has been alot of contamination in my abdominal exploration surgery- what should i put in place?
drain- positive suction is better than a penrose
What are pros and cons of a paramedican approach to the abdomen?
- -less surgical exposure
- -more hemorrhage
- -some think there is less chance of incision breakdown
In flank abdominal surgery when do i enter on the left side? the right?
- left side- for exploratory, (most cases you enter here)
- right side- if you know cecum is the problem
T or F: a flank approach to the abdomen is good for diagnosing the problem, but usually we have to do a ventral midline to fix it anyway
What are signs that the large bowel is the problem? small bowel?
- large bowel- might feel on rectal, no reflux
- small bowel- reflux!
How do i physically locate a large bowel problem in the abdomen during surgery?
- -palpate mesenteric attachment of RD colon and cecum- helps tell if there is a volvulus
- -follow a ventral band cranial and then caudal to the sternal flexure to possibly find prob there
When evaluating the small intestine for problems in abdominal surgery is it better to start cranially or caudally and why?
start caudally- easier to find landmarks like the cecum/cecocolic ligament and then to work forward/orally
Which is more common- primary or secondary gastric dilation?
secondary very common- usually happens with small intestine ileus
In gastric dilation in the horse- should i pass a stomach tube before or after anesthesia and why?
BEFORE- because horse has to swallow the tube and probobly cant do this when under anesthesia
I have opened the abdomen on a colic horse and found that the stomach has ruptured- what do i do now?
euthanasia- when ingesta is free in the abdomen a horse will not survive that degree of peritonitis =(
An owner calls with a foal who is on NSAIDs for another problem, now the foal isnt eating, salivating, looks colicy, and is laying on its back- what do you suspect?
Gastric ulcers that have resulted in a pyloric stenosis!
What is the treatment for a foal with gastric ulcers and pyloric stenosis?
gastrojejunostomy (stomach to small intestine)
How do I diagnose a horse with gastric neoplasia?
endoscopy, or cytology performed on gastric washings
Do we take horses to surgery that have gastric neoplasia? why?
No- equine stomach is very hard to access for surgery
What does simple obstruction mean?
no blood flow is compromised
Ascarid impactions of the small intestine are usually seen in horses how old? why?
- older animals have immune response to ascarids
"Trigger" has an adhesion from a previous abdominal surgery thats causing a simple obstruction in his small intestine- when i open this abdomen to fix this- what can i do to prevent recurrance?
- - suture serosa over the damaged area
- -heparin or carboxymethylcellulose used to minimize adhesion production
- - divert intestines around the adhesion (resection/anastomosis)
What age of horses get pedunculated lipomas?
What part of the country do we see most dital ileum impactions in? why?
- southeast USA
- coastal bermuda grass hay is suspect
How does an abdominal abscess cause a small intestine simple obstruction?
abscess causes adhesions!
Is small intestine neoplasia common? what can be done surgically?
- not much can be done surgically because usually too large to take out sucessfully
- usually euthanized =(
Anterior enteritis clinical signs can look very similar to what? what is the difference?
- small intestine simple obstructions
- anterior enteritis= functional obstruction (no motility)
- SI simple obstructions= mechanical obstruction (somethings in there blocking)
What are some surgical options to help anterior enteritis? what is the goal of these surgeries?
- Jejunocecotomy & Duodenocecotomy
- divert contents of small intestine to large bowel so that the SI has a chance to heal
Strangulating obstructions of SI differ from simple obstructions how?
stragulation obstructions= markedly restricted blood flow
What are some general characteristics of a strangulating SI obstruction?
- - severe lactic acidosis
- -bowel wall becomes permeable- so endotoxins & hemoglobin in peritoneal cavity!
- -animal deteriorates FAST
- - if surgically corrected reperfusion injury can happen
Intussusception of small intestines in most likely to occur at what age of horse? whats the most common place?
What is the definition of a volvulus?
twisting of a segment of bowel on its mesentery so blood flow & intestinal contents obstructed
By what time should i surgically repair a volvulus if i want to leave the bowel in place?
by 6 hours!- or you have to resect and anastomose (usually this happens)
Anatomically what is the epiploic foramen and what are the borders?
- epiploic foramen = entrance to the omental bursa
- dorsal- caudal vena cava
- ventral- portal vein
In epiploic forament entrapment what part of the intestines most likely gets trapped? what is prognosis? what sx can we do?
- usually jejunum
- prognosis poor unless surgery done early- b/c hard to dx
- resection & anastomosis
What are the 2 types of internal hernias?
- 1. epiploic foramen entrapment
- 2. mesenteric defects entrapping bowel
What are 2 embryonic anomalies in the horse small intestine that can cause obstructions?
- 1. meckels diverticulum
- 2. mesodiverticular band
How does Meckel's diverticulum cause a problem in the small intestine?
- - can be axis for volvulus
- - the diverticulum can get impacted and rupture!
What forms a mesodiverticular band?
persistence of distal segment of a vitelline artery and associated mesentery
What does this mesodiverticular band look like anatomically?
extends from one side of mesnetery of jejunum to the antimesenteric side- so it forms a trangular pocket where intestines can get trapped!!!
T or F: umbilical hernias can sometimes present as an acute abdomen?
TRUE- small hernias are more likely to do this compared to large ones
What are the 5 ways we can repair an umbilican hernia in a horse/foal?
- 1. time- correct on its own
- 2. external pressure- belly band to hold it in
- 3. inject mild irritants- iodine & glycerine
- 4. hernia clamp- skin and peritoneum slough off
- 5. surgery- @ 4-6 months old
Are ventral hernias (except umbilical) likely to cause acute abdomen? why?
Not likely because ring is too large to strangulate bowel usually
I am asculting a horse and I think i hear intestinal sounds in the thorax- is this normal?
Can be normal because the diaphragm of horse is so bell shaped
What is a mesenteric thrombus or thromboembolic colic?
thrombus causing reduced or no blood flow to segments of bowel
Simple obstructions of the large colon differ in presentation of simple obstructions of small intestine how?
simple obstruction of colon dont usually look like an acute abdomen
What is the best way to give a horse with a simple colon obstruction that has no gastric reflux fluids?
best to give fluids orally if possible (10Liters per hour)- this is better than IV lfuids
Where do impactions of large colon usually happen?
pelvic flexure or right dorsal colon
I suspect a horse of having an impacted large colon, what signs tell me i need to do surgery on this horse?
intractable pain, excess gastric reflux, unresponsive to medical therapy for several days
What is the general surgical procedure for impacted large colon?
- -ventral midline laparatomy
- - take pelvic flexure out of abdomen and incise
- - put a hose in pelvic flexure and flush out all contents
Impactions of the cecum are usually due to what?
- a motility problem
- occasionally do to hay thats coarse and poor quality
T or F: horses can GET an impacted cecum when recovering from another painful surgery?
true- chronic pain can cause cecum impaction
Enteroliths are usually found where?
- right dorsal colon
- transverse colon
- cranial small colon
What is an example of a non-strangulating displacement of the colon?
nephrosplenic ligament entrapment- Left colon is trapped dorsal to the spleen/nephrosplenic ligament
A horse with nephrosplenic ligament colon entrapment is in what kind of pain?
some pain but not intense (where as if it was a strangulation it would be intense pain)
What is a super cool drug we can give for nephrosplenic entrapement and what does it do?
Phenylephrine- causes spleen to contract so hopefully the colon can slide off and go back to normal position
I have an ancient 20 year old horse and I want to give phenylephrine to help cure this colon entrapment without surgery- what should i be worried about?
fatal hemorrhages reported in horses over 15yrs old!
What are some non-surgical methods we can try to help cure a nephrosplenic ligament entrapment?
- - pick horse up my rear legs so colon moves dorsally
- -put horse in right lateral recumbancy and roll it to dorsal and then continue to left lateral recumbancy
What surgical procedure can i do to prevent nephrosplenic entrapment?
- -close the nephrosplenic space by suturing the base of the spleen to the ligament
- -large colon resection
The large colon is more likely to torse where?
diaphragmatic and sternal flexure
Where is a volvulous of large colon or cecum likely to happen?
just cranial to the mesenteric attachment to the right body wall
Large brood mares right after delivery of a foal are likely to get what surgical condition? what kind of pain are they in?
- large colon volvulus
- extreme pain- may need to anesthetize to do just a physical exam
Horses can do fairly well with how much large colon removed?
up to 90%
"Penelope" is a post-partum friesian horse with a large colon volvulus i just took to surgery, I discovered that the entire cecum is non-viable, what is the next step?
euthanasia- if entire cecum and large colon are non-viable this is the only answer =(
When should a horse suspected of large colon torsion/volvulus be on the operating table for best prognosis?
within 2-3 hours we should be operating!
Rectal prolapse happens most in what species?
What are some causes of rectal prolapse in all species?
- -estrogens in feed relax the anal region
- -high protein diets
- -antibiotics in feed irritate anal area
- -limited exercise
- -bulls housed together
What type of anesthesia do we do to surgically repair a rectal prolapse?
- -caudal epidural in all spp except pig
- -lumbosacral epidural in pigs
What are 3 surgical techniques to fix a rectal prolapse?
- 1. replace and purse string suture
- 2. resect the mucosa
- 3. amputate rectum
How does a rectal ring work for a rectal prolapse?
ring inserted and heavy suture wrapped around so that external part dies and sloughs off- a way to amputate the rectum
Rectal ruptures happen in what species most and why?
- misdirected penis, we did it in a rectal exam!, idiopathic
What is a grade 4 rectal rupture and what is the prognosis?
- #4= thru mucosa, muscularis and serosa
- poor prognosis b/c peritoneum heavily contaminated