Surgery of the small intestine Flashcards
What is the pathophysiology associated with intestinal FBs/obstruction?
- Proximal gas and fluid accumulation
- Air and fermentation
- Inc. salivary, biliary, pancreatic, intestinal
- Decreased absorption due to lymphatic and venous congestion
- Intestinal wall edema
- Prevents vein drainage
- Wall ischemia
- Mucosal sloughing
- Bacterial translocation
How does the pathophysiology of linear FBs differ from non-linear FBs?
- Linear
- Peristalsis carries FB down GIT to form accordian like pleats
- FB embeds in mesenteric border and can perforate intestines
What are the clinical signs of non-linear foreign bodies?
- Vomiting
- Anorexia
- Depression
- Abdominal pain
- Diarrhea
What are the radiographic signs of non-linear FBs?
- Multiple loops of gas-filled dilated intestines
- Ratio–SI diameter/L5 height
- < 1.6 = no obstruction
- > 2 = likely obstruction
What are the clinical signs of a linear FB?
- Vomiting
- Anorexia
- Depression
- Abdominal palpation
- Pain
- Clumping and pleating of intestine
What are the radiographic signs of a linear FB?
- Plicated intestines
- Bunched in central abdomen
- Contrast study
- More obvious pleating
- Teardrop shaped air bubbles
What are the conservative management options for linear foreign bodies?
- Asymptomatic cats
- Free FB from tongue
- 47% success w/o surgery
- Must monitor closely
- Dogs
- Not recommended
- Lodged at pylorus
- 40% have peritonitis at time of sx
What does surgical management of linear FBs consist of?
- Enterotomy
- Free FB cranially from base of tongue or by gastrotomy
- Examine mesenteric border for perforation
- Remove FB through enterotomy
- Catheter technique
- Make 1cm enterotomy in antimesenteric border of proximal duodenum
- Tie FB to catheter and milk down intestines
- Come out anus or enterotomy incision
What are the potential short- and long-term complications of linear FBs?
- Septic peritonitis
- Adhesions
- Dehiscence
- Intestinal ileus
- Short bowel syndrome
- Intussusception
What can cause septic peritonitis from linear FBs?
Dehiscence
How do adhesions occur following linear FB ingestion?
- Caused by disruption of fibrinolytic system
- Ischemia, hemorrhage, infection
- Gentle tissue handling and keep tissue moist to minimize contamination
What are the dehiscence risk factors following linear FB ingestion/removal?
- Technical errors
- Multiple intestinal procedures
- Pre-existing peritonitis
- Lack of omentum
How does intestinal ileus occur following linear FB removal?
- Stimulation of SNS
- Rough tissue handling
- Long surgical time (tissues dry out)
- Extensive
What is intussusception? What are the parts?
- Invagination of one portion of the GIT into the lumen of an adjacent segment
- Parts
- Intussuscipiens = section of intestine on the outside
- Intussusceptum = section of intestine on the inside
- Neck = part of smaller section of intestine protruding from intussusception
- Apex = furthest point of invagination into larger segment of intestine
What are the common locations for intussusception/certain parts?
Proximal and distal?
How is intussusception managed?
- Surgically
- Attempt manual reduction
- If necrotic: resection and anastomosis
- Assess viability
- Perform enteroplication
- Plicate entire intestine except duodenum
What is an enteroplication? What are some complications?
- Suture intestinal loops at 3-5cm intervals w/ interrupted suture along lateral wall
- Avoid tight turns
- Complications
- Obstruction
- Strangulation
- Perforation
What/where are the common intestinal tumors in dogs? Cats?
- Dogs
- Colon and rectum
- Adenocarcinoma most common intestinal malignancy
- Adenomatous polyp most common rectal
- Cats
- SI
- Lymphosarcoma and adenocarcinoma
What are the principles of intestinal surgery suture choices/tissue handling?
- Monofilament synthetic absorbable or non-absorbable
- Less susceptible to infection
- Surgical staples
- Multifilament absorbable
- More tissue drag
- Potentiates infection
- Handle tissues gently
- Intestinal occlusion
- Grasp as little tissue as possible
What are the principles of intestinal surgery closure?
- Submucosa is the layer of strength
- Submucosa apposition results in stronger closure
- Double layer closure not recommended
- Poorer submucosal apposition
- Avascular tissue necrosis
- Increased intraluminal protrusion
What are the principles of suture patterns for intestinal surgery?
- Simple continuous
- Inversion, eversion, or mal-alignment in 38%
- Simple interrupted
- Eversion in 66%
- Modified Gambee
- Approximating pattern
- Inverts mucosa while approximating tissue
- Minimize mucosal eversion–increases risk of infection and adhesion formation
What is omentalization? Why should you perform it?
- Place omentum around area that you have performed a surgical procedure on
- Reasons:
- Angiogenic–faster healing
- Immunogenic–less risk of infection
- Adhesive
- Controls infection
- Lymphatic drainage
- Minimizes leakage
What are the 4 stapling techniques used for intestinal anastomosis?
- Triangular end-to-end (TA stapler)
- Triangular end-to-end (Skin stapler)
- Inverting end-to-end
- Side-to-side anastomosis (
Describe the triangular end-to-end stapling technique
- TA stapler
- Very expensive
- 3 equidistant stay sutures
- Apply tension between sutures
- Fire 3 rows of staples
Describe the triangular skin-to-skin (skin stapler) technique
- Inexpensive
- 3 equidistant stay sutures
- Apply tension between sutures
- Place staples 3mm apart
- Use staples that close tightly
Describe the inverting end-to-end stapling technique
- Uses an EEA and TA stapler
- Place cartridge in enterotomy site 3-4cm from transection
- Place anvil in opposite end
- Tie purse string and fire
- Inverts tissue
Describe the side-to-side anastamosis GIA stapling technique
- Place stay sutures
- Oppose antimesenteric surfaces
- Place stapler in lumen and fire
- TA stapler used to close lumen
- Crotch suture–extra suture sometimes placed down side to prevent leakage
- Quick and easy method
What is short bowel syndrome? What is the pathophysiology?
- Malabsorption and malnutrition that occurs after extensive resection
- Pathophysiology
- Decreased mucosal SA
- Gastric and intestinal hypersecretions
- Decreased intestinal tract transit time
What are the signs of short bowel syndrome?
- Persistent watery diarrhea
- Weight loss
- Contrast agent has 5-12 min transit time
How do you manage short bowel syndrome?
- Fluids and electrolytes
- Parental nutrition
- Small frequently highly digestible meals
- May never resolve
How does the intestine adapt following development of short bowel syndrome?
- Increased enterocyte number and size
- Intestinal diameter
- Increased villus height and crypt depth
What should you aim for when taking an intestinal biopsy? What are the various techniques?
- Full-thickness biopsy wide enough that all layers remain intact
- Sample 3-4mm wide
- Techniques
- Longitudinal biopsy w/ longitudinal closure
- Longitudinal biopsy w/ transverse closure
- Transverse biopsy
- Dermal punch
What are the characteristics of a longitudinal biopsy with longitudinal closure?
- Most common
- Very simple technique
- Elliptical, full thickness incision in the antimesenteric border
How is the longitudinal biopsy w/ transverse closure different than the longitudinal biopsy w/ longitudinal closure (why is it performed)?
- Procedure the same, but close on transverse axis
- Thought to widen intestinal luminal in that area
- Almost impossible if there is any gross pathology of the intestine
- Will actually make the lumen smaller
Describe the transverse wedge biopsy technique
- Full thickness wedge 3-4mm wide taken perpendicular to long axis of intestine
- No more than 20-25% of circumference
What are the advantages/disadvantages of the ultrasound-guided intestinal biopsy technique?
- Advantages
- Obtain sample from any part of the intestine
- Safe and quick
- Can sample lymph nodes or other masses
- Disadvantages
- Insensitive in detecting mucosal lesions
- Can miss focal lesions
- Tumor seeding
- Not used for bladder tumors
What are the advantages/disadvantages to endoscope-guided intestinal biopsies?
- Advantages
- Least invasive
- Able to visualize mucosa
- Disadvantages
- Jejunum out of reach
- No muscular layer
What are the advantages/disadvantages of laparoscopic-assisted intestinal biopsies?
- Advantages
- Can biopsy jejunum and other organs
- Full thickness biopsies
- Disadvantage
- Cannot visualize mucosal lesions
How do you perform an intestinal resection?
- Pack off segments
- Determine extent and ligate blood supply
- Cut mesentery close to vessels of segment
- Occlude proximal and distal segments as atraumatically as possible
- Angle cut to enlarge lumen size to account for 10-20% narrowing during healing
- Minimize mucosal eversion
- Begin at mesenteric border
- Close mesenteric rent
- Omentalize
T/F: Scissors allow for more control but are more traumatic to tissues while a scalpel allows for less control but is less traumatic
TRUE
How can disparity of lumen size be managed when performing an intestinal anastomosis?
- Place sutures farther apart on larger lumen–>causes lumen to crinkle a bit to better suit smaller end
- Cut smaller end of intestine at an angle to increase the SA so it will better line up with the larger diameter lumen
- Fish mouthing–make small incision parallel to long axis of intestine so SA of cut edges lines up better with larger ends
- Suture up excess lumen of larger end so it’ll line up better with smaller end
What is mesenteric torsion? What is the signalment?
- Intestine twisting on mesenteric axis
- Compression of cranial mesenteric arteries
- Ischemic necrosis of all intestine
- Signalment: male german shepherd of any age
What is the etiology of mesenteric torsion?
- Unknown
- Lymphocytic enteritis
- Ileocolic carcinoma
- GIT foreign body
What are the clinical signs of mesenteric torsion?
- Abdominal distension
- Hematochezia
- Collapse and death
How do you diagnose mesenteric torsion?
- Shock patients with distended abdomen not relieved with tube
- Radiographs show gas-filled intestines with normal stomach position
- Necropsy
- D/D GDV
What is the treatment for mesenteric torsion?
- Crystalloids and colloids
- Immediate sx to untwist torsion
- Determine intestinal viability and resect if necessary
What is the prognosis for mesenteric torsion?
- Rare disease with high mortality
- Once thought to be nearly 100%
- Early sx leads to higher survival rate
What is serosal patching and when is it used?
- Securing an antimesenteric border of small intestine over a suture line or defect
- Indications
- When omentum is unavailable
- Closure integrity is questionable
- Non-resectable duodenal defects
- Enterotomy, colostomy, urinary bladder
- Mucosa spans defect within 8wks
