Lecture 5 & 6: Sx of the Intestines (Exam 1) Flashcards
Define enterotomy
An incision into the intestine
Define enterostomy
Removal of a segment of intest
Define intestinal resection & anastomosis
An enterostomy w/ reestablishment of continuity btw/ the divided end
Define intestinal plication (enteroeneteropexy)
Surgical fixation of one intestinal segment to anoth
Define enteropexy
Fixation of an intestinal segment to the body wall or another loop of intestine
Define colopexy
Surgical fixation of the colon
Define colectomy
Partial or complete resection of the colon
Define typhlectomy
Resection of the cecum
Define colostomy
Surgical creation of an opening btw/ the colon & the surface of the body
Define tenesmus
Straining to defect
Define dyschezia
Pain or discomfort on defecation
Define hematochezia
Passage of stolls that contain red blood
Define melena
Passage of tarry stools (digested blood)
What is the most common indication of SI sx
GI obstruction
What are other indications of sx on the SI
- Trauma
- Malpositioning
- Infection
- Dx/Supportive procedures
What are some indications for a GI obstruction in the SI
- Tumors
- Intussusception
- Foreign bodies
- Masses
What are some indications of trauma to the SI
- Perforation
- Ischemia
What are the indications for sx of the LI
- Obstruction (tumors, intussusception, granulomatous masses)
- Perforation
- Colonic inertia
- Chronic inflammation
What does a visual exam provide info about
- Mental status
- Temperament
- Nutritional state
- Comfort
What can abdominal palpation ID
- Pain
- Thickened intestine
- Masses
- Mispositioned organs
Where can the colon be palpated
Dorsocaudal abdomen
T/F: the sublumbar LN enlargements are always palpable
False; they maybe be palpable
What can a rectal exam show in the LI
- Shape & symmetry of the pelvis
- Mucosal thickness
- Pelvic canal masses
- Intraluminal masses
- Distal strictures
- Thickening/enlargement/pain of the anus or anal sacs
What needs to be done pre op for px undergoing intestinal sx
- Obtain min database (CBC, Chem profile, urinalysis, etc.)
- Localize the lesion w/ palpation, radiographs, etc.
- Correct hydration, electrolyte, & AB abnorms
- Transfuse if the PCV is < 20% or is if the px is weak/debilitated
- With hold food for 12 - 18 (mature) or 4 - 8 (pediatric) before induction
- Admin prophylactic antibiotics if indicated
T/F: Most animals w/ large bowel disease have no lab abnorms
True
What are some rare lab abnorms seen in LI disease
- Dehydration
- Electrolyte changes
- Anemia
- Hypoalbuminemia
What radiograph views should be taken for SI disease
- Lateral recumbent
- Ventrodorsal projection
What is done before contrast studies & why
- Abdominal ultrasound
- B/c it often provides the Diagnosis & allows the contrast study to be circumvented
What is the preferred imaging modality
Ultrasonography
What are clotting factor deficiencies treated w/
Whole blood or FFP
When is emergency exploratory sx indicated w/out delay
- Px deteriorates clinically despite aggressive medical management
- Complete obstruction, perforation, strangulation, necrosis, or sepsis is suspected
Which part of the GI contains the most bacteria
Colon
What should be done during pre op if working on the colon/LI
Pre-op colonic emptying & cleansing indicated to reduce bacterial load unless a perforation/obstruction is suspected
What are other ways to decrease bacterial loads in the colon
- Feeding an elemental diet
- With holding food for 24 H
What is an elemental diet
- A diet that proposes the ingestion, or in more severe cases use of a gastric feeding tube or IV feeding, of liquid nutrients in an easily assimilated form
- Composed of AAs, fats, sugars, vitamins, & minerals
What is a caution of enemas
Given any closer to sx than 3 H pre op may liquefy intestinal content & add to the dissemination of contaminated material during sx
Describe the disadvantages of enemas
- Can further deteriorate debilitated & anorectic px
- May cause colonic perforation
- May be ineffective in cates w/ megacolon
- Never give hypertonic phosphate enemas to small or constipated px
What surgeries are classified as clean contaminated or contaminated depending on the amount of spillage
Sxs that involve entering the intestinal lumen
What causes a increase infection in contaminated wounds
- Px stress
- Organisms pathogenicity
- Tissue susceptibility
- Time
Describe clean contaminated wounds
Operative wounds in which the respiratory, GI, or Genitourinary tract is entered under controlled conditions w/out unusual contamination or w/out significant spillage of contents
Describe contaminated wounds
Open, fresh, accidental wounds; procedures in which GI contents or infected urine is spilled or a major break in aseptic tech
When are prophylactic antibiotic indicated
- Animals w/ intestinal obstruction b/c there is an increased risk of contamination assoc w/ bacterial growth
- When devascularized & traumatized tissue is present
- When sx is expected to last long than 2 - 3 H
What is the risk of infection after colorectal sx
high
What is systemic periop abx effective against
- Anaerobes
- Gram (-) aerobes
What suture is used in intestinal sx
- Monofilament, synthetic absorbable suture
- Like polydioxanone & polyglyconate
What needle is used in intestinal sx
Swaged on taper or taper cut point needle
What does intestinal sx need for optimal healing
- Good Bs
- Accurate mucosal apposition
- Min surgical trauma
What can system factors increase
- amount of healing time
- Risk of dehiscence
- Hypovolemia
- Shock
- Hypoproteinemia
- Debilitation
- Infection
What suture patterns are used
- Simple interrupted
- Gambee
- Simple cont
- Stapling tech are feasible
What does the submucosa do
Is the intestinal layer that provides mechanical strength so it must be engaged when suturing intestine to provide a secure closure
What are the two principles of intestinal sx
- Cover sx site w/ omentum or serosal patch
- Replace contaminated instruments & gloves before closing the abdomen
What is done for an approximating suture closure of the intestine
- Place simple interrupted sutures 2 mm from the edge & 2 to 3 mm apart
- Engage slightly more serosa than mucosa to evert the mucosa into the lumen
What suture patten is this
Gambee
What are the advantages of an enterotomy for bx
- Allows access to the entire GI tract
- Provides full thickness bx
- Can examine & sample the rest of the abdomen @ the same time
What are the disadvantages of doing an enterotomy for bx
- Most expensive & invasive
- Don’t allow one to detect mucosal lesions
- Doesn’t allow one to obtain as many mucosal samples as an endoscopy
- Is possible to take nondx tissue samples if the proper tech is not followed
What are the steps of an intestinal bx
- Occlude the lumen than make a stab incision into the lumen w/ a No. 11 blade
- Removew a 2 to 3 mm ellipse of tissue w/ metzenbaum scissors or make a second incision approx parallel to the first w/ a scalpel
- Close the incision w/ simple interrupted sutures
How is an enterotomy closed
- Like a biopsy
- May be closed transversely if the intestinal lumen is small (joint the extremes of the incision w/ a simple interrupted; place the remaining sutures 2 to 3 mm apart)
How is a small intestinal resection & anastomosis done
- Place forceps transversely across the dilated proximal intestine & obliquely across the distal intestine
- Ligate the vessels
- Transect the intestine & mesentery
- Place the 1st suture @ the mesenteric border & the second @ the antimesenteric border
- Additional interrupted sutures are placed to complete the anastomosis
- Appose the mesentery in a simple cont pattern
Describe an end to end anastomosis using a modified simple cont pattern
- Place & tie appositional sutures @ the mesenteric & antimesenteric borders (leave the needles attached)
- Using the suture tags as stay sutures to maintain tension place a cont suture pattern btw/ the antimesenteric & mesenteric sutures
- Reposition the intestine & begin a second cont suture line on the oppo side
Describe stapled anastomosis techs
- More expensive than sutured anastomosis
- Less tissue interaction
- More mature fibrous connective tissue
- Greater tensile strength
- Fewer mucoceles
- Fewer necrotic areas
- Less luminal stenosis
List the 4 stapled anastomosis techs
- Triangulating end to end
- Inverting end to end
- Side to side/functional end to end
- End to side anastomosis
What is this
TIA stapling Device (Transverse intestinal stapler)
List the steps of a triangulating end to end anastomosis
- Place three stay sutures that appose the ends of the intestine & divide the circumference into three equal parts
- Apply tension btw/ two of the sutures & fire the stapler leaving a double staggered row of sutures
- Apply tension btw/ the next two sutures & position the stapler so it overlies the end of the first row of staples & fire again
- Repeat for a third time
Describe how to do an end to end anastomosis
- Use an end to end anastomosis stapler & a transverse stapler
- Insert the stapler cartridge into the intestinal lumen through an enterotomy to 3 to 4 cm from the transection site
- Insert the anvil into the other intestinal end
- Tie purse string sutures securely around the shaft of the stapler
- After the anastomosis close the enterotomy w/ sutures or a transverse stapler
What is this
Side to side or functional end to end staplers
What is this
Reloadable GIA 60 stapling device
What is this showing
Side to side or functional end to end anostomosis
What is intussusception
The telescoping or invagination of one intestinal segment (intussusceptum) into the lumen of an adjacent segment (intussuscipiens)
Where is the most common places intussusception occurs
- ileocolic
- Jejunojejunal
What is the cause of most intussusceptions
Unknown
Is intussusception in cats or dogs more likely
- More likely associated in cats w/ neoplasia than in dogs
- Cats are usually older than affected dogs
What are the key points of Box 45 intussusception
- Young animals after getting parvoviral enteritis is most affected
- Major cause of protein-losing enteropathies in young dogs
- Older animals w/ masses
- Usually w/ enteritis or systemic illness
- Signs: partial to complete obstruction
- Invagination is normograde but can be retrograde
- Ultrasound shows a target or bull’s eye pattern (concentric intestinal layers)
- Manually reduce or resect & anastomose
- Enteroenteropexy prevents recurrence
What are the segments of the large bowel
- Cecum
- AC
- TC
- DC
- Rectum
What is a major concern when performing colonic sx
Blood supply
What are two additional principles for LI sx
- Reduce colonic bacterial #s by eliminating oral intake, preparing the colon, & giving abx
- Dehiscence is more likely w/ large bowel sx than w/ small bowl sx
What are some surgical techs for the LI
- Dehiscence is more likely
- Bowel viability can be difficult to asses
- Necrotic or avascular areas must be removed
- Avoid unnecessary resection
- Resection & anastomosis is performed w/ sutures or stable
Describe a colopexy
- Create permanent adhesions btw/ serosal surface of the colon & the abdominal wall
- Prevent causal movement of the colon & rectum
- Usually used to treat chronic recurring rectal prolapse
- Can be done w/ laparoscope
What is a complication of a colopexy
Infection resulting from suture penetration of the colonic lumen
What is the tech of a colopexy
- Locate & isolate DC
- Pull colon cranially to reduce prolapse
- Verify reduction by nonsterile assistant
- Make 3 to 5 longitudinal incision through only the serosal & muscularis layers along the antimesenteric border of the descending colon
- Make a similar incision in the left abdominal wall several cm lateral to the linea alba through the peritoneum & underlying muscle
- Ciomplete pexy w/ simple continuous pattern of 2-0 or 3-0 monofilament absorbable suture
- Lavage the surgical site
- Wrap w/ omentum before closing
What are colectomy & resection used for
Primarily for colonic mass removal & megacolon
What are other indications for a colon resection & anastomosis
- Trauma
- Perforation
- Intussusception
- Cecal Inversion
What % of the colon can be resected in animals w/out adverse side effects
Up to 70%
Who can tolerate colonic resections better than dogs
Cats
Describe subtotal colectomy
- removal of 90% to 95% of the colon
- Often done in cats
- Avoided in dogs
- Warn owners that after the cat probably will defecate freq & have soft stools
What is colonic resection & anastomosis used for
- Exploratory
- Collect non intestinal specimens
Describe how to form a colonic resection & anastomosis
- Isolate the diseased bowel w/ laparotomy pads
- Assess viability & determine resection sites
- Double ligate all vasa recta vessels to disease segment
Milk fecal material from the lumen of the isolated bowl - Occlude the lumen @ both ends to minimize fecal contamination
- Place another forcep across each end of the diseased bowel
- Transect through healthy colon
What is a sutured anastomosis
- One or two layered closure
- 3-0 or 4-0 monofilament absorbable or non absorbable suture
- Simple interrupted sutures through all layers w/ extraluminal knots
Why is an angle needle needed
So that slightly more serosa than mucosa is engaged to prevent mucosa from protuding btw/ sutures
T/F: sutured anastomosis tech are essentially like those used in a small intestinal sutured anastomosis
True
What should be done if there is minor disparity btw/ the lumen sizes ina sutured anastomosis
Space the sutures around the larger lumen slightly further apart than the sutures in the segment w/ the smaller lumen
What should be done after a sutured anastomosis
- Check for leakage by mod distending the lumen w/ saline & applying gentle digital pressure
- Look for leakage btw/ sutures or through suture holes
- Place additional sutures if leakage occurs btw/ sutures
- close the mesenteric defect
- lavage the isolated intestine
- Remove the laparotomy pads & change gloves/instruments
- lavage the abdomen w/ sterile warm saline the suction it out
- Wrap the site w/ omentum or create a serosal patch
When is a two layered anastomosis done
If there is tension @ the anastomotic site
How is a two layered anastomosis different than a one layer
- The serosa & muscularis are apposed in a separate layer
- All sutures engage the submucosa
Where are the layers of simple interrupted sutures placed in the two layered anastomosis
- First layer: placed to appose the mucosa & submucosa, & the knots are tied w/in the lumen
- Second layer: apposes the muscularis & sersoa then the knots are positioned extraluminally
What can the distal colon be anastomosed
- Ileum
- Jejunum
What are the indications for a Typhlectomy
- Impacted cecum
- Inverted cecum
- Perforated cecum
- Neoplastic cecum
How can the location of the cecum be ID
By a small indentation where it can be palpated w/in the colonic lumen
How is a typhlectomy done
- Double ligate the cecal branches of the ileocolic vessels
- Dissect the ileocecal fold of the mesentery
- Place a clamp across the base of the cecum near the cecocolic orifice & transect
- Close the colonic defect w/ simple interrupted sutures
What is a megacolon
Persistent increased large intestinal diameter & hypomotility associated w/ severe constipation
Define idiopathic megacolon
If mechanical, neurologic, or endocrine cause cannot be IDed
Define constipation
Difficult or infrequent defecation w/ passage of unduly hard dry fecal material
Define obstipation
Extreme constipation (no feces may be passed)
Describe megacolon
- Most common in cats
- Clinical signs (not a specific dx)
- Congenital or acquired
- Prolonged severe colonic distension eventually causes irreversible changes in the smooth muscle & nerves causing inertia
What is the main cause of megacolon
Idiopathic
What is the diameter of a mega colon
Greater than 1.5 times the length of L7
How is a subtotal colectomy fixed? How do dogs & cats handle them
- W/ a subtotal colectomy
- Cats often handle it well
- Dogs don’t handle it well
Describe the healing of the LI
- Like the SI but delayed
- Dehiscence is more likely
- Wound tensile strength lags behind the SI
- Stapled anastomoses have higher bursting pressure & higher tensile strength
- Min inflammation & double row of staples increase wound strength
What is the post op for LI intestine
- Monitor for vomiting or regurgitation
- Pain control
- Monitor & correct for electrolyte & AB abnorms
- IV fluids until eating & drinking
- Abx discontinued 4 to 6 hours post op (unless contamination/infection)
- Small amts of water @ 8 to 12 H post op
What is the most common complication of GI sx
Hemorrhage & fecal contamination of the abdomen
