---start---
medsurg3
11/9/98

brockman -
a bit more biliary tract surgery

then surgery of rectum and anus

back to biliary disease - there is stuff 
in notes that doesn't make sense - on page 3 of the hepatic sx notes, it 
says hepatocellular carcinoma is about 50% of single large hepatic masses 
esp in dogs >104 yrs old but it should say 10 years. then under diagnosis 
it says serum alk phos may be elevated and some other stuff but bottom 
line is serology is very variable. under clinical features change 
hypocalcemia to hypercalcemia. 

surgical conditions of extrahepatic 
biliary tract: fibrosing pancreatitis
don't get bogged down in mechanics 
of the operations.
cholecystoduodenostomy - excellent choice for chronic 
fibrosing pancreatitis obstructing biliary flow through duct. object of 
this is to make a big stoma b/w gall bladder and duodenal lumen. 


Billroth II operation - can divert bile in conjunction with larger 
gastroduodenal resections - gastroenterostomy is performed. proximal 
duodenum is resected so bile duct/pancreatic duct were ligated, so now 
you do cholecystojejunostomy. you can't do this in cats because their 
pancreatic flow all goes through major duodenal papilla.

Trauma to 
biliary tract:

blunt abdominal trauma: recall can cause bladder rupture, 
renal trauma, hepatic trauma...biliary tract can also be disrupted. most 
often, dog is HBC, comes in and gets stabilized, responds well to 
emergency measures, gets sick 3-5 days later. this is common presention 
of bile peritonitis secondary to gall bladder rupture. abdominocentesis 
reveals bile in peritoneum. it's important when evaluating to determine 
if there is bacteria present as well - bacterial and bile peritonitis 
together has a worse prognosis.

slide: what you'd see at surgery - 
greenish/yellow color to everything.

these animals aren't absorbing fat 
soluble vitamins and stuff so be careful - K is fat soluble.

slide: 
another example of this.

surgical measures -
remember, gall bladder can 
be repaired or removed.
the cystic duct can be repaired, or the gall 
bladder can be removed
the hepatic duct can only be ligated. ligate on 
both sides and bile flow from affected lobe will occur through 
collaterals.
the common bile duct is most common site of injury. can be 
repaired in large dogs, although it is hard. or, it can be ligated and 
then you have to do a bypass procedure. 

slide: t-tube in place in 
repaired common bile duct.

cholecystitis/cholangitis: most of the 
abdominal trauma cases that lead to bile peritonitis will not involve 
bacterial infection and will respond well to definitive therapy and tx 
for peritonitis. there are other things though that can predispose to 
biliary tract rupture under otherwise normal conditions or during trauma. 
cholecystitis/cholangitis - may cause chronic signs of vague malaise, 
intermittent v/d, etc. this is chronic  biliary infection. typically see 
elevated liver enzymes, hyperbilirubinemia. if gb has ruptured 
spontaneously will present with biliary peritonitis and bacterial 
peritonitis with coliform bacteria being common in septic bile 
peritonitis. this spontaneous rupture is unlike traumatic rupture.
these 
dogs have a very difficult recovery after surgery which typically 
involves ensuring patency of ducts and removing gall bladder - but they 
have raging septic peritonitis, hard to tx.

curiosities: cystic mucinous 
hypertrophy is sometimes seen - these two slides show cystic mucus plugs 
that sat in the gall bladder of a dog who presented with vague signs of 
intermittent vomiting and hyperbilirubinemia. pathogenesis related to 
chronic biliary stasis due to inflammatory disease. pigment forms plugs 
and mucus accumulates around them and they cause intermittent complete 
biliary obstruction as they float into a duct. tx is cholecystectomy. 


complications of biliary tract surgery include leakage, recurrent 
cholangitis, reflux of intestinal contents, pancreatic insufficiency 
(cats)(exocrine due to ligation of duct and endocrine due to secondary 
pancreatitis)

in humans, many operations have been developed to reduce 
risk of reflux from cholecystoenterostomy - one involves resection of 
small intestine with an end to side anastomosis of duodenum to jejunum, 
wand a sort of blind loop created  - doesn't really work.

end of 
extrahepatic biliary surgery section. 
moving on quickly to rectal stuff.


colorectal and anal disease in the cat and the dog: dr holt already 
talked about the colon, and as part of that lecture he talked about 
carcinoma of the rectum. we will skim over that. we will concentrate now 
on different things. remember anatomy - as described for perineal hernia 
- is important. local muscles - innervation, blood supply. rectum really 
is terminal two cm or so of large intestine. is divided into most caudal 
part - columnar zone - and more proximal mucosal zone. columnar zone 
contains goblet cells which can get hyperplastic in disease states. so 
rectum is limited in ways it will respond to disease processes. 
innervation, presence of goblet cells, pretty much mandate that signs of 
colorectal disease are always similar:

signs:
tenesmus
dyschezia 
(difficulty defecating)
hematochezia aka haematochezia

constipation/obstipation
diarrhea aka diarrhoea

slide: proper 
positioning of animal for rectal surgery (on rectal stand)

slide: dog 
butt. look carefully at this anal orifice and you see a mucocutaneous 
junctiono dividing perineal skin from rectum - that's columnar zone. they 
are cannulating the anal sacs here - at 4 and 8 o clock in relation to 
anal orifice. dz of sacs == impaction, infection, neoplasia. so excision 
is performed for chronic impaction or infection or tumor or involvement 
in other diseases. 

it might be hard to get a feel for when you want to 
recommend anal sac resection for anything other than neoplasia. clearly 
the anal sacs get blamed for a lot. when you find nothing wrong with the 
dog, usually you can find something wrong with the anal sacs :). it's a 
convenient organ from that point of view. but seriously, they rarely 
cause a problem. they are normally emptied at defecation, a few times a 
day. they surely can get impacted and cause perineal irritation. other 
things do that also - parasites, neoplasia, etc. scooting requires a 
thorough evaluation, not just assumption that it is impaction of anal 
sacs. 

if dog comes in q 6 mos to have anal sacs emptied, fine. but if 
dog has to come in 3 x month, think about surgical excision.

in notes it 
describes 2 techniques for resection of anal sacs. in the literature 
there are descriptions of multiple techniques some including placement of 
warm wax through the duct, to make sac more obvious. some people like to 
put cotton wool in there to distend it. he likes to use a probe placed 
through duct, dissect it out over the probe. it isn't important which 
technique you use as long as you do it carefully. most important 
structure you could interfere with is the caudal rectal nerve. a few 
times a year we see cases of dogs who had anal sac resections and ended 
up fecally incontinent. this is irreversible. so be careful. another 
technique described in notes Dr B has not done. instead of placing probe 
in duct into sac, place scissor blade in there and cut, allowing you to 
lay it open and resect it. this is fine, you won't damage the nerve, but 
he prefers the other way. circumferential incision over sac with 
something in sac so you can find the limit of the sac. it is a very 
vascular area, limits of sac are not that clear, so it is sometimes hard 
to do this surgery but you should be able to. 

slide: postop - two 
sutures in place.

now and then, an animal presents with an abscessed 
anal sac. this one here spontaneously ruptured. do not try to resect a 
sac in this environment. abscessed sacs with spontaneous rupture usually 
respond well to surgical drainage and tx with systemic abx based on c/s 
results. then after inflammation is gone you can resect it. you probably 
want to resect the healthy one too. 
in notes, it says to instill 
intramammary antibiotics - first line of tx before surgery would be to 
use those bovine intramammary abx infused into the sac. i think he means 
into the sac. do good flush, get culture, use local/systemic abx therapy, 
prior to commiting to surgical tx. 

tumors of anal sacs are always 
malignant. anal sac adenocarcinoma is seen most often in middle aged to 
older female spayed dogs. male dogs can get them as well. signs are 
variable. this is sort of like LSA or mammary CA b/c it makes a PTHrP 
which can cause hypercalcemia. sometimes they present with signs relating 
to the tumor - tensemus, hematochezia, etc. others will present with 
signs related to the PTHrP with neprogenic DI and be PU/PD.  yet another 
reason to do rectal exams as part of your routine PE on all of your 
patients. if you are in the habit of routinely doing rectal exams, you 
won't miss these tumors. 

these tumors also cause pulmonary mets - 
fluffy, ill defined increased density areas with some nodular formations, 
throughout pulmonary parenchyma. sx tx of these dogs is aimed at 
controlling local dz, or getting tissue diagnosis. 

slide: huge 
sublumbar LN and abdominal mets. 
sometimes if you catch it early and you 
resect the tumor and there is LN enlargement causing signs of 
constipation, resecting the LNs can be palliative. can also control 
metastatic dz, reduce signs of hypercalcemia. but this isn't curative. 
it's palliative. more mets will show up. but can extend quality time up 
to 12 mos.

slides: sometimes these tumors occur in cats; generally cats 
have more healthy anal sacs so this is rare in cats, but it can occur. 
this other slide is another cat perineum showing another dz process 
looking neoplastic - this is eosinophilic granuloma dz, though.

moving 
away from anal sac dz...into Rectal Tumors:

rectal carcinoma:this is a 
slide of a dog with presenting complaint hematochezia, dyschezia, mucus 
on feces, red mass popping in and out of anal orifice.this is a pinkish 
mass with some surface hemorrhage. fairly pedunculated. is a benign 
rectal polyp (they biopsied it so they know this).best biopsy technique 
is to place allis tissue forceps and prolapse the terminal rectum - these 
usually have a nice long stalk but even if not can remove to level of 
rectal mucosa with scissors or cautery, to get adequate sample for path 
lab. remember - benign polyps, CIS and carcinoma are probably stages of 
the same disease. so you do excisional biopsy. 

slide: another poodle, 
same history and presentation - they pulled this out on its stalk and 
resected it - but this turned out to be a leiomyosarcoma. 

another one - 
this is carcinoma

another dog that presented with straining, 
hematochezia, and large ulcerative lesion in rectal wall - carcinoma. tx 
of carcinoma == local resection. concern is the high metastatic potential 
- you have to really stage the animal carefully first. if distant disease 
is present, sx may be indicated if owner is contemplating chemo or just 
to relieve clinical signs, but usually once mets are present tx is 
unrewarding.

three sx approaches to rectum: dorsal approach, where 
incision is made dorsal to rectum, over anal opening, and terminal 
rectum/colon is mobilized. can excise distal 5-6 cm this way.
ventral 
approach requiring splitting the pelvis is most aggressive, involved 
approach. this isn't for general practice situation. none of these are, 
really.

pull through approach - this dog has a carcinoma - this 
procedure makes incision around the mucocutaneous junction of anus, 
rectum is dissected 360 degrees around, and pulled out through anal 
orifice. then it is transected and sutured back to skin. don't get bogged 
down with details at this point.

rectal carcinoma most worrisome

leiomyosarcoma can occur
remember progression from polyp to cis to ca


most common perineal tumor is perianal adenoma - benign tumor of perianal 
hepatoid glands, seen most commonly in intact  males. these are androgen 
dependent tumors. may occur around anus or on tail, leg - these glands 
are found in a few areas. may be on prepuce. these can present as 
multiple small subcutaneous nodules, or as single huge masses. often 
ulcerated. very malodorous. these lesions when small will often respond 
simply to castration. the big ones require resection. try and resect 
these so as to minimize anal distortion. use incisions radiating away 
from the center of the anus. these masses are generally subcutaneous. 
since you will castrate at the same time they shouldn't recur. should 
have good result. 

we talked about intestinal disease before - remember 
it is important to determine the difference b/w a prolapsed rectum and 
passage of a large intussusception. remember you tell this by attempting 
to pass a blunt, well lubed probe, b/w the rectum and structure. with 
intussusception probe goes way in. with prolapse, it does not. tx for 
prolapse is usually one of three things.

rectal prolapse occurs in 
unthrifty, heavily parasitized animals, so first figure out why straining 
so hard - maybe you have to worm this animal or whatever. then, clean off 
rectum, sometimes place hypertonic sugar solution on it or whatever, to 
reduce edema, then replace, and place pursestring with room for passage 
of feces. 

if rectum is dessicated, or there is a lot of mucosal 
erosion, there is an intermediate option - simply resect necrotic area of 
mucosa but leave submucosa and muscularis intact. suture healthy mucosa 
back together then proceed as above. 

final option - amputate the 
prolapse, then suture healthy tissue to healthy tissue in two layers. in 
cats, rectal amputation is poorly tolerated and associated with massive 
straining to the point of passing out the entire small intestines. cats 
can't have this procedure. you can't amputate feline rectums. so for 
recurrent prolapse in cat you can perform surgical recuction by opening 
peritoneal cavity, pulling colon cranially, and suturing colon to the 
body wall with sutures of proline or other permanent suture. 

perianal 
sinuses and fistulas - almost always in GSD, rarely in gordon setter, 
irish setter, more rarely in working collie dogs. this is the formation 
of multiple sinuses and fistulae b/w rectal wall and anal sacs. 
frustrating to treat. also tracts b/w anal sacs and perianal skin. 
theories about this - some say it has to do with tail carriage clamped 
tight over perineum in these dogs, creating bacterial proliferation; also 
presence of massive anal crypts is implicated; some people think this is 
really an anal sac disease; more people now are thinking this is an 
immune mediated dz, because it responds to immunosuppressive therapy. 


slide: mild case - traditionally treated by surgical resection of 
diseased areas and associated anal sacs with healing by contraction and 
epithelializatino. however, the literature suggests nonsurgical tx like 
high dose pred and abx has some success. also cyclosporine. Dr B says, as 
with any complex poorly understood dz, each case varies and best 
treatement for each case varies. some dogs probably will still require 
sx.

---break---

donawick

COLIC - equine acute abdomen

Equine 
abdominal pain - how to tell apart a life threatening problem from a 
problem that will resolve on its own.

you will hear about this from 
medical and surgical perspectives, but obviously dr D will talk about 
surgical perspective.

Colic == a painful digestive disturbance. that's 
all it means. but that's the word we use for the equine acute abdomen. 
usually only baby humans and horses are described as having colic. in the 
horse, the vet has to stay up and work...

Specifically what are colics? 
alterations in intestinal motility resulting in accumulations of fluid 
and gas. so if you see a colicky horse, it has either a motility change 
resulting in accumulation of gas and fluid, which stretch the GI tract 
and cause pain - the more intestine is affected, the more painful it is. 
years ago, Dr D made these experimental ponies where you took an 
intestinal loop outside the body and you'd put stuff in it and watch the 
absorption rates and stuff, and sometimes distend them with helium - and 
this would create pain. 
they used 2 foot sections. a little bit of 
helium in there resulted in a big pain reaction immediately. opening the 
valve and releasing the gas immediately relieved the pain. 

if you could 
get hillary to stop working on her computer, and could bring her up on 
this table and lay her out there, and even use some local anesthesia and 
put in aline block near her belly button and put down a cutting board and 
took out some of her small intestine, and put it on the board, and she 
was still awake, and you took a blade and cut the intestine, she 
shouldn't feel it. b/c intestine doesn't have cut receptors. it only has 
stretch receptors. if you pull on mesentery, that might hurt. you can 
massage the intestine, wiggle it, etc and the animal will not feel it. 
you just have to block the body wall - then you can go in there and move 
stuff, incise, etc. you do not have to anesthetize the intestine and as 
long as it isn't distended it will not hurt.

um, i am sensing some 
hostility against me.

Colic - it is hard to find a disease with as many 
causes as colic. Dr D sees 200-300 cases each year - after 35 years you'd 
think that he'd find a pattern. but there isn't one. 

primary causes of 
colic:
abrupt changes in feed
overfeeding
migration of parasites

obstruction of intestine by parasites
infectious disease
acute torsions 
and obstructions

study in texas - Dr Cohen - what he did was to look at 
horses, tried to find out the cause of colic. 
spasmodic or gas colic 
(medicine cases ) - 29%
colonic impaction - 20.7%
the rest were all from 
1-5% - many causes.
ileal impaction, cecal impaction, unknown, other, 
torsion, etc.

insignificant factors - these did not predispose horse to 
colic:
outdoor v indoor, bedding, hay, grain, dental care, vaccination, 
all these have no effect. also frequency of anthelmintics, number of 
anthelmintics, rotation of anthelmintics, use of ivermectin - none of 
this mattered. 

important factors: stabling changes, recent diet 
changes, activity level, history of previous colic or abdominal surgery.


odds ratio: 

hx of pervious colic - 5x more likely to recur
hx of 
previous abdominal sx - 5x more likely to colic
recent change in diet - 
2x more likely
recent change in stabling - 1.2 x more likely
recent 
change in activity - 1.2 x more likely

management changes to reduce 
colic:
drinking water should be available at all times when outdoors

carefully train relief help
insist on your schedule and management style


the incidence of colic was increased when the owner wasn't there and care 
was delegated to someone else, like weekend help, which didn't feed at 
the same time of the day. horses like routine. they want it to stay the 
same all the time. 

when a manager hires someone, they have to be strict 
about having things done the same way. doesn't matter what is done as 
long as it is consistent. 

predisposition to abdominal crisis - why is 
horse predisposed?
-long mesenteric attachment of small intestine - horse 
intestine is on a long mesentery, can wander around abdomena nd get 
trapped in bad area. cow has short thick mesentery by comparison so do 
not colic. 
-virtually all blood supply to inteine through one blood 
vessel - the anterior cranial mesenteric artery
-large colon so 
voluminous it must fold in three places to fit inside the abdomen

-hairpin turns and rapid narrowing  - narrowest spot is transverse colon.

-cecum is enormous - food comes in side, has to go out top into right 
ventral colon
-nerve supply to intestine lies adjacent to artery most 
often damaged by parasites. so artery can get inflamed and affect nerve 
and alter motility.

rule of thumb: cecum and appendix are on the right 
side. the only other thing to remember is that food is heavy when it 
first arrives, then things get absorbed and food is lighter so it will 
rise. from cecum we go into right ventral colon - heavy, falls down into 
there. still heavy so goes forward and is near the sternum so it goes by 
sternal flexure. goes right to left, still heavy, then into left 
ventricle, comes back along left side, back to the back to the pelvic 
flexure. now getting lighter so rises up left dorsal colon. then up 
toward front again past diaphragmatic flexure. then it moves into right 
dorsal colon, crosses through transverse colon, into small colon. 
transverse colon is narrowest site.

diagnostic philosphy: concentrate 
efforts to determine if colic is life threatening. maybe 8% are life 
threatening. the others you have time. so it is like looking for a black 
spaghetti in a bowl blindfolded. 

suspect life threatening lesion when:

susteained HR 60 or more - should be 28-40 beats per minute
gastric 
reflux
abdominal distension: only two things cause this - all small 
intestine is distended or all large intestine is distended. with ascites 
would be pear shaped. distension from intestines is round like apple. if 
horse has duodenitis, jejunitis, won't get distended. might have reflux 
and pain but won't distend. 
return of pain soon after xylazine: one 
reason we like to use xylazine is b/c it wears off and it wears off 
pretty fast. we need a drug that won't mask signs too long or we delay 
therapy too long. give 300-500 mg xylazine IV for pain. if it wears off 
in 10 minutes, that's bad, b/c it means there are a lot of pain signals 
heading to the brain. 
cardiovascular collapse: low BP, congested MMs. 
slow CRT, rising PCV
bloody peritoneal fluid: serosanguinous fluid is 
bad. red is bad. you must collect the fluid yourself though b/c someone 
could hit a vessel and make it look bloody and then you don't know...

displaced or twisted intestine: if you feel this on rectal, that's bad.


slide: horse - kinda round - has torsion of large colon

obvious 
abdominal distension is only caused by distention of ALL the small or 
large intestine.

treatment philosphy - when in doubt, assume the worst 
case scenario. better to treat. do not wait and see how it is tomorrow. 


don't rely on the "dark" philosophy: the sun is going down and i've got a 
million things to do so I will refer it though i held onto it all day but 
i don't want to stay up all night so i will refer.

today's reality: 
there is a magic window of opportunity. it starts to close at 12 hrs, and 
is shut tight at 24 hrs. if horse has lifethreatening intrabdominal 
lesion, you have 12 hrs to deal with it. when does window start? at onset 
of clinical signs. if you wait over 24 hrs, most horses go to horse 
heaven. 

simple mechanical obstructions: compromise of bowel lumen 
without compromise of vascular supply: overall survival rate about 75%. 
duration of signs not critical to survival in these horses  - exception - 
abscesses have high mortality. 

strangulating obstruction - compromise 
of vascular supply to bowel with or without lumen compromise. overall 
survival rate 53%. duration of signs critical to survival. within 12 hrs 
- 80% survival. 12-24 hrs - 50% survival. >24 hrs, <15% survival. so you 
want to see these animals early but consider - owner checks horse at 7 
pm, feeds, waters, horse is fine. then horse colics a minute after owner 
leaves. owner comes back in am at 8 am and finds horse in distress. 12 
hrs are already over. 

now a horse dies when so many cells die that the 
horse can't live. when the whole bowel turns black, you're in big 
trouble.

there is a client named dan who is very lucky - he brings in 
horses that should not survive and they survive. why? b/c the minute 
anyone on the farm suspects colic he puts the horse on the trailer to 
come here. so he gets them in early. 

how to decide:
history, PE, 
rectal, abdominoparacentesis, response to initial therapy.
listen 
carefully to what people say - they will not use medical jargon, but they 
will give real clues. the PE can't be skipped. you have to do it. gather 
information. the rectal is also very important. abdominal paracentesis is 
crucial. gathering fluid and checking. 

Breed related colics:

thoroughbred: incarceration of small intestine in epiploic foramen 
(opening into the omental bursa) bordered by liver, pancreas, posterior 
vena cava. it's amazing but somehow the ileum of the TB goes into that 
hole and gets stuck. TB may have a smaller caudate lobe.
standardbred: 
incarceration of small intestine in inguinal canal. this is an indirect 
hernia. 96/100 of these are in standardbreds

age related colics:
young 
horses under 3 yrs old. volvulus of small intestine, intussusception of 
small intestine, ileocecal intussusception. those three things affect 
young horses mainly. probably, parasite related. altered motility, etc. 


older horses > 8 yrs
torsion of large colon, incarceration of small 
intestine in epiploic foramen - an old TB disease though to be related to 
change in caudate lobe maybe.
strangulation of intestine by pedunculated 
lipoma - ball of fat on extension growing out from mesentery - wraps 
around and ties off intestine.

when you do a rectal, you can't feel the 
cranial GI tract, so you can miss huge things b/c you can't feel them. 
you can barely reach the kidneys. 








---end----