Common SA and LA GI Surgical Techniques Flashcards
describe GI surgery reasons
- non-strangulating obstruction:
-intraluminal: FB, impaction, fecalith, trichophytobezoar
-intramural: masses (neoplasia, inflammatory, infectious)
-extraluminal:displacements (abomasal, large colon) - strangulating:
-volvulus: GDV, mesenteric/segmental SI, LCV, AV
-intussusception
-other: epiploic foramen entrapment, strangulating lipomas
what are the types of GI surgery?
- remove contents:
-alleviate distension, remove obstruction, remove source of endotoxin
-needle decompression for gas, move SI contents into cecum (horse), enterotomy (rumen, stomach, SI, cecum, colon, high enema (horse)) - resection and anastomosis
-remove compromised intestine, prevent recurrence - correct positioning:
-alleviate obstruction of GI +/- blood supply - pexy: prevent recurrency
when do we go to surgery for SA cases?
- evidence of foreign material that is causing an obstruction
-presence of gastric foreign material that could cause an obstruction - ID of a possible resectable GI mass
-don’t always know before surgery from imaging alone if can resect it all - presence of intususception
- obstruction present with an unknown cause
- presence of GDV
when do we go to surgery for LA?
- diagnosis of a strangulating lesion
- nonstrangulating lesion not responding to medical management
3, other lesions not responding as expecting or unable to reach diagnosis
- clinical signs:
-pain!!
-persistent abnormalities
-systemic deterioration
list 5 rules for ALL GI surgeries in SA
- pack off section of GI tract to be opened from the rest of the abdomen
-with sterile moistened lap pads - gentle tissue handling is a MUST
-debakey tissue forceps if anything
-if don’t have use rat tooth - change gloves prior to closing the abdomen
-decrease risk of surgical site infection - do not use instruments used on GI tract to close the skin
- flush the abdomen
list rules for ALL GI surgeries in LA
- exteriorize segment of GI tract to be opened and drape off from the abdomen
-with sterile moistened lap pad +/- split sheets - minimize tissue trauma
-care with mesentery, amount of pressure on intestine as exteriorize/manipulate
-use of carboxymethylcellulose (belly jelly) to decrease trauma when squeezing intestines to decrease adhesions
-appropriate forceps, wet 4x4 - separate instruments and change gloves (usually gown too) after any surgery opening GI tract
- lavage intestine prior to returning to abdomen +/- lavage abdomen
- lavage incision between layers
describe ventral midline celiotomy
- most common approach for horses and pigs
-less common for GI surgery in small ruminants or camelids
-rare for GI surgery in cattle - incision through linea alba from umbilicus cranially (adult ~25-30cm)
-minimal hemorrhage and strong tissue for closure
-closure: simple continuous pattern in linea
-SQ and skin as one or two layers
describe GI anatomy of ventral midline exploratory laparotomy
stomach:
-where: left cranial
-cannot exteriorize
-if you can see it depends on stomach size and incision position
-ID via palpation: shape/location
duodenum:
-where: extends from pylorus to right side, around cecum, across midline, and cranial
-cannot exteriorize
-cannot see it
-ID via finding pylorus and duodenocolic ligament
jejunum:
-can be anywhere
-can exteriorize and see all but most oral segment
-ID by tracing from ileum orally to duodenocolic ligament
ileum:
-attached to cecal base dorsally
-can exteriorize and see aboral portion
-ID by finding ileal cecal band (dorsal band of cecum)
describe GI anatomy of ventral midline exploratory in the horse
cecum: PRESENTING ORGAN OF ABDOMEN
-where: right dorsal flank to cranial ventral
-cannot exteriorize or see base/cupula
-ID: PRESENTING ORGAN, bands, blind ended
large/ascending colon:
-right cranial, across to the left, left caudal
-can exteriorize 70-80% of it
-can see all but oral right dorsal part
-ID via cecocolic band: lateral band of cecum
transverse colon:
-where: dorsally, crossing abdomen, cranial to root of mesentery
-cannot see or exteriorize it
-ID: trace from right dorsal colon or from small colon
small/descending colon:
-can be anywhere
-can exteriorize and see most/mid section
-ID: fecal balls, wide antimesenteric band
describe the paramedian and paracostal approach
- paramedian:
-location:
–horse: 10cm either side of midline at similar level to ventral midline
–cattle: cranial right, 6-8cm caudal to xiphoid, 4-6cm right of midline
-layers: skin, SQ, external rectus sheath, rectus abdominus, internal rectus sheath, peritoneum
-closure: focus on external rectus sheath for body wall (holding layer), +/- SQ, skin
-GI accessibility/indications:
–horse: similar access to ventral midline, previous ventral midline still healing, esp if infected; colopexy
–cow: abomasal access, abomasopexy
- right paracostal:
-cattle and camelids
-access to abomasum/C3
describe flank laparotomies
- most common approaches for ruminant GI surgeries
-few applications for horses - incision: center paralumbar fossa (~25cm in adult cow)
-can be vertical or on diagonal
-can drift cranial (stay at least hand behind rib) and/or ventral - layers: skin, SQ, external abdominal oblique, internal abdominal oblique, transversus abdominis, peritoneum
- closure:
-peritoneum and transversus abdominis
-internal oblique (can combine with previous layer)
-external oblique (holding layer)
- +/- SQ
-skin
describe GI anatomy of flank laparotomies
right flank:
1. present organ: descending duodenum in greater omentum
-not with DA or AV!
2. GI accessible:
-pyloric portion abomasum/C3 (esp if drift cranial), and adjacent omentum
-most SI and LI
-can palpate reticulum and omasum
left flank:
1. presenting organ: rumen
2. GI accessible:
-rumen
-reticulum through rumen
-abomasum if LDA
describe gastrotomy
- indications:
-gastric FB not retrievable via endoscopy
-gastric biopsy
-linear FB anchored in stomach - incision location:
-on ventral surface between greater and lesser curvature
-avoid pylorus and blood vessels - closure:
-2 layer closure: common
–submucosa/mucosa layer: simple continuous patter
–seromuscular layer: simple continuous OR cushing (inverting) pattern
-1 layer closure: simple continuous or inverting pattern
-holding layer = submucosa!!!!!! (MUST CATCH OR WILL DEHISS)
describe enterotomy
- indications:
-obstructive foreign material in SI with viable intestine and no evidence of leakage or compromise of intestinal wall integrity
-intestinal biopsy of SI - rules:
-in addition to other 5, ALWAYS leak test intestinal segment: 5cm on either side of closure, target pressure is 15-25mmHg, if using digital/finger clamps use 12mL saline or 10mL if using doyen clamps (if leaking, place more sutures)
-omental wrap or serosal patch recommended in all cases
- incision made aborad to FB, antimesenteric border (away from blood supply), because FB already moved through orad segment so she is angry, want to go into healthy intestine aborad
-use doyens or assistant fingers to prevent intestinal content leaking
-holding layer = submucosa
-mucosa should NOT be everting through incision after closure
- suture: 4-0 PDS or biosyn (long lasting, absorbable), taper needle (so can use needle to tuck mucosa in)
-pattern: simple interrupted, modified Gambee, simple continuous
-NO inverting patterns (will cause stricture or narrowing)
-suture bites: 3-5mm from edge and from each other
NEVER EVER EVER DO ENTEROTOMY IN LARGE INTESTINE (if made it to colon, it’s probably going to make it out)
describe rule differences for LA intestinal surgeries
- most use inverting, continuous patterns
-less concern for lumen size then in SA
-but more concern for leakage - omental patches are extremely uncommon
-adhesions are a significant clinical complication
-omentum often involved
-omentectomy frequently performed
describe -otomies in LA
- locations:
-rumen/C1, abomasum/C3
-SI (jejunum)
-LI (cecum, spiral colon, LC (pelvic flexure most common), SC)
-antimesenteric for SI, colons - closure:
- 2-0 or 3-0
-double layer
–first layer: mucosa or full thickness simple continuous
-oversewn most commonly partial thickness continuous inverting pattern (cushing or lembert) in seromuscular/submucosa
-single layer: skip first layer
-similar bite distances as SA
when do we do a resection?
- nonviable intestine
- intestine leaking: esp at mesenteric border
- intestinal masses
when can we NOT perform a resection?
- area to be resected involved the common bile duct or pylorus
- mass or area of concern extends to the root of the mesentery (would lose entire intestinal tract if resect)
- so what do? have a convo with owner during surgery, if not leaking maybe can wake up and see what happens, if leaking consider intra-op euthanasia (hopefully warned owner before)
describe intestinal R&A closure
suture: 3-0 or 4-0 PDS or biosyn
pattern:
-simple interrupted or continuous, NO INVERTING
holding layer = submucosa
same distances for bites as enterotomy
describe complications of GI surgery in SA
- dehishence!!
-3-5 days post op (debridement phase of healing)
-enterotomy: 3.2-3.8% in dogs
-R&A: 18% in dogs
-numerous risk factors: hypoalbuminemia, hypotension, ASA >3, older age - adhesions
- short bowel syndrome if take out a lot
describe R&A in LA
- almost always for a strangulated portion
-other reasons: masses, adhesions, strictures - SI end to end (SC similar)
-handsewn
-similar to -otomy closure
-most do continuous interrupted at 180 degrees
-some surgeons use interrupted patterns - jejuno-cecostomy:
-end to end or side to side
-handsewn or staple - large colon:
-end to end or side to side
-hand sewn and stapled
-also used to prevent recurrence of displacement or volvulus
-want mesenteric side to be very for sure closed!!!
-start sutures at antimesenteric side to preserve lumen size
-ligating mesentery: CAN ligate large vessels bc many many feet of smaller vessels to ligate would take way too much time (in SA want to ligate smaller vessels if you can)
describe surgical treatment for GDV
abdominal exploratory surgery:
1. correct gastric malpositioning:
-pylorus will be on left side of the abdomen
-omentum will be covering the stomach
-grasp pylorus and gently pull ventrally and toward yourself on the right side
-pass OGT after derotation
- assess for active bleeding:
-may see a hemoabdomen upon entry into the abdomen, often not active bleeding though
-short gastric vessels can get ripped during rotation or derotation: check there first! can ligate if actively bleeding - determine gastric and splenic viability
-fundus/cardia are most commonly affected
-after derotation, allow time for bloodflow to return before making any decisions
-assess color and wall thickness: thin wall = risk for perforation
-does bleed when cut?
-if devitalized portion of stomach, remove and partial gastrectomy
-colors same as intestinal viability
-spleen: feel splenic artery for pulses, look at color of spleen, if no pulses and/or it dark black/cold even after derotation and time, take it out - gastropexy: create a permanent adhesion from the stomach to the body wall to prevent recurrence
-incisional: technically easy, good adhesion formation, use absorbable monofilament (PDS or Maxon-long lasting); risk of perforation
–cut seromuscular layer only
–incision at pyloric antrum!!
-belt loop
-circumcostal
-tube
-incorporating
describe GDV outcome
- mortality 10-27%
-multifactorial
-may have to euth intra-op due to extensive gastric necrosis - risk of dehiscence/septic peritonitis post-op
-other complications: arrhythmias, DIC, ileus, vomiting - low risk of recurrence with appropriate gastropexy
describe LA -pexies
horse:
-large colon: prevent recurrence of LCV and displacements
–risk of rupture is low but fatal if occurs: most avoid in performance horses
cows:
1. prevent recurrence of displaced abomasum or AV
2. many approaches (including laparoscopic)
3. abomasopexy: right paramedian or left flank, omentopexy (right flank), pyloropexy (right flank)
4. non surgical: roll and toggle
