Exam 1: Lecture 5/6 - Surgery of the intestines Flashcards
what is the definition of enterotomy
an incision into the intestine
what is the definition of enterostomy
removal of a segment of intestine
what is the definition of intestinal resection and anastomosis
an enterostomy with reestablishment of continuity between the divided cells
what is the definition of intestinal plication (AKA enteroenteropexy)
surgical fixation of one intestinal segment to another
what is the definition of enteropexy
fixation of an intestinal segment to the body wall or another loop of intestine
what is the definition of colopexy
surgical fixation of the colon
what is the definition of colectomy
partial or complete resection of the colon
what is the definition of typhlectomy
resection of the cecum
what is the definition of colostomy
surgical creation of an opening between the colon and the surface of the body
what is the definition of tenesmus
straining to defecate
what is the definition of dyschezia
pain or discomfort on defecation
what is the definition of hematochezia
passage of stools that contain red blood
what is the definition of melena
passage of tarry stools (digested blood)
what are the indications for SI sx
- GI obstruction (via tumors, intussusception, FB, masses)
- trauma (perforation and ischemia)
- malpositioning
- infection
- diagnostic/supportive procedures (biopsy, culture, cytology, feeding tubes)
what are the indications for sx of the LI (large intestine)
- obstruction (tumors, intussusception, granulomatous masses)
- perforation (colonic inertia, chronic inflammation)
what does visual exam provide us with
mental status, temperament, nutritional state, comfort
what can abdominal palpation help ID for SI issues
pain, thickened intestine, abdominal masses, or mispositioned organs
what do we look for on PE of large intestine
- colon is normally palpable
- feces vs masses on palpation
- sub lumbar LN enlargement may be palpable
- lyphadenomegaly suggestive of metastasis
- rectal exam
what are the things we look for on rectal exam
- shape and symmetry of pelvis
- mucosal thickness
- pelvic canal masses
- intraluminal masses
- distal strictures
for the PE of the LA, should we palpate anus, anal sacs, and do a fecal exam?
yes!!! look for thickening, enlargement, pain, blood, mucous, or parasites
what are the most important things to do for preoperative management of intestinal sx
- obtain minimum database
- localize lesion
- correct hydration, electrolyte, and acid-base abnormalities
- transfusion if needed
- withhold food
- administer prophylactic abx if needed
why do we do hematologic and biochem profiles prior to SI sx
to ID concurrent systemic disease like renal, hepatic, hypoadrenocorticism, hypercalcemia, diabetes mellitus, or pancreatitis
other than finding underlying disease, why else can hematologic and biochem profiles be helpful
to direct preoperative therapy
T/F: abnormalities should be corrected prior to anesthesia if possible
true!! better for the patient if we are able prior to sx
T/F: most animals with large bowel disease will have similar findings to animals with SI issues
false, they dont usually have any lab abnormalities
what can survey rads potentially show us for SI issues
- abnormal gas-fluid patterns
- masses
- FB
- abdominal fluid
- displaced viscera
what can contrast studies show us for SI issues
FBs, obstructions, abnormal displacement, abnormal bowel wall thickness, irregular mucosal pattern, distortion of bowel wall
T/F: abdominal ultrasound is typically done prior to contrast studies
true!!
T/F: survey rads of the LI rarely help patients with diarrhea
true!! but may help with megacolon
why have barium enemas have been replaced with colonoscopy
it is MUCH safer
what is the preferred imaging modality
ultrasound!!
what does gastroduodenoscopy allow visualization and biopsy of
visualization and biopsy of duodenum
what does colonoileoscopy allow visualization and biopsy of
ileum
what can visualization of intestinal mucosa detect
ulcers, erosion, infiltrated mucosa and/or lymphangiectasia
what is endoscopy more sensitive in diagnosing compared to rads
masses, ulcers, infiltrates, and intussusceptions
describe characteristics of colonoscopy
- safe
- noninvasive
- more sensitive to diagnose masses, ulcers, infiltrates, intussusceptions
what is the preop management for intestinal sx
- correct for hydration, acid base, and electrolyte deficits
- blood transfusion if PCV <20%
- clotting factor deficiencies treated with fresh whole blood or fresh frozen plasma
the benefits of stabilizing animal prior to sx must be weighed against what 2 thing
risk of ischemic necrosis and risk/presence of septic abdomen
T/F: if animal deteriorates clinically despite aggressive medical management and complete obstruction, perforation, strangulation, necrosis, or sepsis is suspect…..emergency SX is indicated without delay
true!! Need to get in there for sx if you are trying to stabilize and they are not getting better
for LI sx, what is important to remember about the colon
it contains MORE bacteria than the rest of the GI tract
T/F: pre-op colonic emptying and cleansing is not needed prior to sx
false, it is indicated ti reduce bacterial load UNLESS perf of obstruction is suspected
what is an elemental diet
a diet that proposes the ingestion, or in more severe cases use of gastric feeding tube, of liquid nutrients in an easily assimilated form. it is composed of AAs, fats, sugars, vitamins, and minerals
what are the 3 things given 24 hours prior to LI
- laxatives
- cathartics
- warm water enemas
what is the best combination for cleansing colon
electrolyte solution and enema
why should we use caution on the amount of time we give enemas prior to sx
if you give an enema less than 3 hours pre-op, it may liquify intestinal content and add to the dissemination of contaminated material during sx!!
what are the 4 reasons to not give enemas
- can further deteriorate debilitated anorectic patients
- may cause colonic perforation esp in cats
- may be ineffective in cats with megacolon
- never give hypertonic phosphate enemas to small or constipated patients
T/F: the risk of infection in contaminated wounds increases with patient stress
true!!
what is a clean-contaminated wound
operative wounds in which respiratory, GI, or genitourinary tract is entered under controlled conditions without unusual contamination or without significant spillage of contents
what is a contaminated wound
open, fresh, accidental wounds or procedures in which GI contents or infected urine is spilled or a major break in aseptic technique occurs
when are prophylactic abx indicated
- in animals with intestinal obstruction
- when devascularized and traumatized tissue is present
- when sx is expected to last longer than 2-3 hrs
T/F: risk of infection after colorectal sx is low
false, it is high!!
T/F: systemic perioperative abx is effective against anaerobes and gram neg aerobes should be given
true!!!
what type of suture should we use for intestinal sx
monofilament, synthetic absorbable suture like PDSII (polydioxanone), Maxon (polyglyconate), monocryl (poliglecaprone), biosyn (glycomer 631)
what type of needle should we use for intestinal sx
swaged-on taper or taper-cut point needle
T/F: optimal healing requires a good blood supply, accurate mucosal apposition, and minimal surgical trauma
true!! should always have these things during sx
how can we prevent most complications for intestinal sx
early diagnosis and good surgical technique
what can systemic factors do to patients who get intestinal sx
delay healing, increase risk of dehiscence, hypovolemia, shock, hypoproteinemia, debilitation, and infection
what type of suture patterns should we use for intestinal sx
- simple interrupted (MOST COMMON)
- crushing
- gambee
4, simple continuous - stapling techniques but can be expensive
what layer of intestines gives the mechanical strength
submucosa
what are the principles of intestinal sx
cover surgical sites with omentum or a serosal patch and replace contaminated intruments and gloves before closing abdomen
what do we do for approximating suture closure
place simple interrupted sutures 2mm from the edge and 2-3 mm apart
what is the purpose of closing intestines like this
keeps mucosa from coming up or anything else
whats the suture pattern
gambee suture pattern
what are the advantages of enterotomy for biopsies
- allows access to entire GIT
- provides full thickness biopsies
- can examine and samples rest of abdomen at the same time
what are the disadvantages of enterotomy for biopsies
- most expensive and most invasive
- does not allow one to detect mucosal lesions
- does not allow one to obtain as many mucosal samples as flexible endoscopy
- it is possible to take nondiagnostic tissue samples if proper technique is NOT followed
what are the 4 steps to an intestinal biopsy
- occlude lumen, make stab incision with #11 blade
- remove 2-3mm ellipse of tissue
- make 2nd incision approx parallel to the first with scalpel
- close incision with simple interrupted
This is an intestinal FB in a cat. Why do we only see white gauze around it
because this segment has been exteriorized and packed off from the rest of the abdomen with moist laparotomy sponges to maintain asepsis
how do we close an enterotomy
like a biopsy or closed transversely if the intestinal lumen is small
what is happening in this picture
leak testing of the enterotomy site
T/F: we dont have to always leak test after an enterotomy
false, we ALWAYS have to leak test
what are the steps to small intestinal resection and anastomosis
- place forceps transversely across dilated proximal intestine and obliquely across distal
- ligate vessels
- transect intestine and mesentery
- place first suture at the mesenteric boarder and second at antimesenteric boarder
- place additional simple interrupted sutures to complete anastomosis
what is being shown in this picture
an end-to-end anastomosis using a modified simple continuous pattern
what are the advantages of stapled anastomosis techniques
- less tissue reaction
- more mature fibrous connective tissue
- greater tensile strength
- fewer mucoceles
- fewer necrotic areas
- less luminal stenosis
what is a disadvantage of stapled anastomosis techniques
more expensive!!
what are the 4 stapled anastomosis techniques in the SI
- triangulating end-to-end anastomosis
- inverting end-to-end anastomosis
- side-to-side or functional end-to-end
- end-to-side anastomosis
what is this
TIA stapling device
what stapling technique is this picture showing
triangulating end-to-end anastomosis
what stapling technique is this picture showing
inverting end-to-end anastomosis
what stapling technique is this picture showing
side-to-side or functional end-to-end
what is this device
reloadable GIA 60 stapling device
what stapling technique is this picture showing
side-to-side or functional end-to-end
what part of the side-to-side or functional end-to-end technique is this
“putting on the pants”
what part of the side-to-side or functional end-to-end technique is this
“putting on the belt”
what is an intussusception
telescoping or invagination of one intestinal segment (intussusceptum) into the lumen of adjacent segment (intussuscipiens)
what causes most intussusceptions
we dont know!!
where are the most common spots for intussusceptions
ileocolic and jejunojejunal intussusceptions
T/F: intussusception in a cat is more likely associated with neoplasia than in dogs
true!!
what is a KEY POINT of intussusception
ultrasound reveals target or bulls-eye pattern
what is this picture showing
A is showing an intussusception and in B it is reducing intussusception
what are the segments of the large bowel
cecum, ascending colon, transverse colon, descending colon, rectum
T/F: blood supply is not a big concern when performing colonic surgery
false, it IS a major concern
what are 2 additional principles of LI sx
- reduce colonic bacterial numbers by eliminating oral intake, preparing the colon, and giving abx
- dehiscence is more likely with large bowel sx than with small bowel
T/F: it can be difficult to asses viability of the bowel
true!! we also must remove necrotic or avascular areas
T/F: resection and anastomosis is performed with sutures or staples and we should avoid unnecessary resection
true
what is the purpose of doing a colopexy
- create permanent adhesions between serosal surface of the colon and abdominal wall
- prevent causal movement of colon and rectum
- used to treat chronic recurring rectal prolapse
what is a complication of colopexy
infection resulting from suture penetrating of the colonic lumen
what is the general technique of colopexy
- locate and isolate descending colon
- pull cranially to reduce prolapse and verify reduction
- make 3-5 cm longitudinal incision through only the serosal and muscularis layers along the antimesenteric boarder of descending colon
- makes similar incision in left abdominal wall lateral to linea alba
- complete pexy with simple continuous pattern with 2-0 or 3-0 monofilament absorbable suture
when is colon resection and anastomosis primarily used
for colonic mass removal and megacolon
T/F: up to 70% of colon can be resected in animals without adverse side effects
true!!
T/F: dogs tolerate colonic resection better than cats
false, cats tolerate better than dogs
T/F: subtotal colectomy is done in the cat but should be avoided in dogs
true!! we are removing 90-95% of the colon
for sutured anastomosis, do we use 1 or 2 layer closer
either or! we do NOT do two layer in SI
what type of suture and suture pattern should we use in sutured anastomosis
3-0 or 4-0 monofilament absorbable suture (can also use nonabsorbable) and sinple interrupted sutured through all layers
T/F: sutures anastomosis in the LI is essentially the same as those used in SI
true!!
What should we do if there is a small amount of disparity of the lumen sizes
space sutures around the large lumen slightly further apart than the sutures in the segment with the smaller lumen
After we finish LI sutured anastomosis, what should we do???
- check for leaks!!
- place additional sutures if leakage occurs
- close the mesenteric defect
how do we leak test sutured anastomosis in LI
lavage isolated intestine thoroughly without allowing fluid to seep into abdominal cavity
what should we do if there is tension at the anastomotic site
a 2-layer closure…it is performed like a one-layer closure except that the serosa and muscularis are apposed in a separate layer
what is being shown in this picture
stapled anastomosis with triangulation technique and skin stapler
what can the distal colon be anastomosed to
ileum and jejunum
what are the 4 techniques of stapled anastomosis in LI sx
- inverting end-to-end anastomosis
- side-to-side or functional end-to-end
- end-to-side anastomosis
- triangulation technique and skin stapler
when should we do a typhlectomy (cecal resection)
- impacted cecum
- inverted cecum
- perforated cecum
- neoplastic cecum
the cecum is inverted into the colonic lumen….what procedure should we do
typhlectomy
what is megacolon
persistent increased LI diameter and hypomotility associated with severe constipation
what is idiopathic megacolon
if mechanical, neurologic, or endocrine cause cannot be ID
what is constipation
difficult or infrequent defecation with passage of unduly hard, dry fecal material
what is obstipation
extreme constipation (no feces may be passed)
what animal is megacolon most COMMON in
cats!
T/F: megacolon can be congenital or acquired
true!
T/F: Megacolon is described when the diameter of the colon is greater than 1.5 times the length of L7
true!!
when should we do a subtotal colectomy for megacolon
when medical management becomes unsatisifactory
what is a subtotal colection
removal of the entire colon except a short distal segment needed to reestablish intestinal continuity
what are the 2 view points over removing the ileocolic jinction
- removal allows for colonic microorganisms access to SI with subsequent malabsorption and increased diarrea
- preservation minimizes post-op diarrhea but may allow for recurrence of constipation
T/F: Colostomies are regularly done in animals
false, they are seldomly indicated but can be performed as a radial treatment
T/F: The LI heals quicker than the SI
false, LI heals slower
T/F: LI is more likely to dehisce compared to SI
true!
when do stapled anastomoses have a higher bursting pressure
during the early lag phase of healing
when do stapled anastomoses have higher tensile strength compared to hand-sutured
after 7 days
what are some of the post op care for intestinal sx
- monitor for voming or regurg
- pain control
- correct electrolyte or acid-base abnormalities
- IV fluids until eating and drinking
- abx discontinues 4-6 hours post op
- can give bland food after 12-24 hours post op
what are the most common complications of intestinal sx
hemorrhage and fecal contamination of the abdomen are most common
other than hemorrhage and contamination, what are the 8 other complications of intestinal sx
- shock
- leakage
- dehiscence
- perforation
- peritonitis
- stenosis
- incontinence
- death
