Ch 92 small intestine Flashcards
A carnivores SI is approx how long?
Approx 5 times the length of its trunk
1 - 1.5m in cats
2 - 5m in dogs
Anatomy
- duodenum along the right side of the abdomen (contains intrasmural bile duct, major and minor duodenal papillae)
- caudal duodenal flexure > triangular attachment of the initial part of the ascending duodenum is called the duodenocolic ligament
- left of the root of the mesentery duodenojejunal flexure
- mesojejunoileum is more commonly known as the mesentery > short peritoneal attachment known as the root of the mesentery
- root of the mesentery includes the cranial mesenteric artery, intestinal lymphatics, and large mesenteric plexus of nerves
- Nearly all of the intestinal blood supply is supplied through the cranial mesenteric artery, anastamoses with celiac and caudal mesenteric
- cranial mesenteric vein arborizes in the mesentery and collects blood from the jejunum, ileum, and caudal duodenum before terminating in the distal portal vein. The gastroduodenal vein drains the proximal duodenum
- nerve fibers to the mesenteric portion of the small intestine come from the vagus and splanchnic nerves
- ranial mesenteric ganglion is located on the sides and caudal surface of the cranial mesenteric artery
- clustered around the root of the mesentery are five or six large mesenteric lymph nodes
Where does the root of the mesentery attach?
L2
Within which layers of the SI does the vascular network run?
Beneath the serosa and within the submucosa
small intestine is structurally composed of four layers:
the mucosa,
- villi that increase the surface area approximately 8-fold in dogs and up to 15-fold in cats
- surface cells are of two types: columnar cells = absorption, and goblet cells = mucus-producing
- lymphoid follicles are grouped together to form aggregated follicles known as Peyer’s patches.
submucosa
- supporting skeleton of the gut
- Small blood vessels, lymphatics, and the submucosal nerve plexus
muscularis
- outer longitudinal layer and a thicker inner circular layer
serosa
- composed of the peritoneum
How often does the inner intestinal lining (villus epithelium) completely replace itself?
every 2-6 days
What are the 2 types of contraction seen in the small intestine?
Segmental contraction - Mixes ingesta
Peristaltic contraction - Moves ingesta aborally
local and vagally mediated (parasympathetic nervous system regulates)
What percentage of the water presented to is does the jejunum and ileum absorb?
Jejunum - 50% of presented water absorbed
Ileum - 75% of presented water absorbed
How do glucose and galactose enter the enterocyte?
Fructose?
Taken up by cotransport with Na via the transporter GLUT1
Fructose via GLUT2
physiology
- most water-soluble compounds such as amino acids and monosaccharides require membrane carriers to allow absorption through the intestinal mucosa.
- Cells at the base of the villus are dividing, undifferentiated epithelial cells (fluid secretion)
- differentiate into immature enterocytes as they pass up the crypt
- tip of the villus, lose secretory capacity > digestion and absorption.
- Absorption of sodium: passively across the jejunum or coupled with Na+-K+/ATPase–mediated active transport of monosaccharides or amino acids
- Digestion is achieved using a combination of enzymes from the small intestinal luminal brush border cells and the pancreas (trypsin, amylase, lipase) and, for fat digestion, bile released from the gallbladder
What electrolyte derangements are common with GI obstruction?
Hypochloraemia, Hyponatraemia and Hypokalaemia
- metabolic acidosis common
- Vomiting > excessive loss of gastric fluids rich in potassium, sodium, and hydrochloric acid,
- resulting in a hypochloremic, hypokalemic metabolic alkalosis
Fluid Therapy
- nimals with gastrointestinal disease often present with preexisting imbalances that must be corrected before surgery
- Preoperative treatment of hypovolemia resulting from intestinal obstruction or ileus consists of intravenous infusion of balanced electrolyte solutions and correction of severe acid-base and electrolyte abnormalities
- Surgical fluid losses occur from tissue damage during dissection and from evaporative losses, which are significant during intraabdominal surgical procedures
Fluid and electrolyte needs should be reassessed frequently after surgery.
Antibiotic Prophylaxis
- normally contains Gram-positive and Gram-negative organisms.
- antibiotic should be appropriate for the bacteria at surgical site (i.e., the proximal versus distal small intestines).
- in the tissues at the time of surgery
- first-generation cephalosporins remain one of the most effective
surgical approach
- midline
- laparoscopic-assisted: ventral midline subumbilical trocar cannula using a modified Hassan technique or a single-port device, bowle is exteriorised through skin (certain bowel segments (proximal duodenum, duodenal flexure) have limited mobility and cannot be adequately exteriorized)
How can fluoroscein be used for assessing SI viability?
Give 10-15mg/kg IV - results in wide distribution within minutes and full urinary excretion 24-36hr. Using a Woods lamp in darkened surgical suite, patchy areas with non-fluorescence >3mm indicates loss of vascularity
Assessment of Intestinal Viability
- many clinical criteria can either overestimate or underestimate
- presence of peristalsis, vascular pulsations, and intestinal color do not necessarily correlate with the histologic severity
- objective measurements of viability, such as surface oximetry or fluorescein infusion
Choice of Suture Material for Enteric Closure
- Monofilament synthetic absorbable (polydioxanone, polyglyconate) or nonabsorbable (nylon or polypropylene) sutures and staples are excellent choices
- Monofilaments are less susceptible to bacterial adhesion and allow easier clearance of bacteria by host defense mechanisms compared to mutifilament
- Absorbable knotless barbed suture
- inflammation at an incision site prolong the lag phase of wound healing and delay return of strength (all material do this to some degree)
What suture pattern can correct mucosal eversion when closing the GIT?
Modified Gambee pattern - Must be able to properly identify the submucosal layer for this pattern to be appropriate
Choice of Suture Pattern for Enteric Closure
- good submucosal apposition can result in primary intestinal healing with direct bridging of the defect.
- Submucosal apposition is poorer with two-layer closure than single-layer closure
- Two-layer closures also result in avascular necrosis of the inverted cuff of tissue (prolongs the lag phase of wound healing) and increased intraluminal protrusion (prone to obstruction)
- everting patterns are more likely to elicit adhesion formation.
- Approximating suture patterns: histologically in 66% of simple interrupted closures, and inversion, eversion, or misalignment of tissues is seen in 38% of simple continuous closures
- Simple interrupted, simple continuous, and modified Gambee
- full-thickness 3 to 5 mm from the tissue edge and 3 to 5 mm apart, with extraluminal knots
- STUDY: comparing simple interrupted and continuous patterns found a low and comparable rate of enteric leakage with either pattern
- surgeon’s knot provides excellent grip and security, particularly when using the slippery monofilament materials recommended for intestinal surgery
- too loose healing by second intention, too tight/crushing inhibits angiogenesis and impedes healing as well.
Suture Line Reinforcement
- omentum
- omentum sutured in placed around an anastomosis is more likely to prevent leakage than chance contact
- forms an adherent sheath that is capable of preventing perforation and fatal leakage and of revascularizing the region - serosal
- jejunal serosal patch has been called the surgical parachute
- shown, experimentally and clinically, to reliably seal contaminated and grossly infected intestinal perforations in dog
- sustained significantly higher intraluminal pressures before leakage,
- use of a serosal patch did not influence the rate of continued peritonitis or death
- Gallbladder serosal patch for defects in the proximal duodenum has shown promise in experimental studies
What are the properties of omentum which make it good for reinforcing your suture line?
Omentum has an extensive vascular and lymohatic supply and exhibits angiogenic, immunogenic and adhesive properties
What has been shown as the length of bowel and volume of saline to use for a leak test to simulate peristaltic pressure in small-medium dogs with digital occlusion? With Doyens?
- 10cm segment of bowel
- 16-19ml saline with digital occlusion
- 12-15ml saline with Doyens
All anastomoses can be made to leak with sufficient pressure
Intestinal Resection and Anastomosis
indications: for removal of ischemic, necrotic, neoplastic, granulomatous, or stenosed segments of intestine
- hand-sewn single-layer, simple interrupted approximating suture pattern
- 3-0 or 4-0 monofilament suture
- first and second sutures placed at the mesenteric and antimesenteric borders
- modified continuous pattern (imited retrospective report compares favorably with reports of complications from other techniques)
disparity between the luminal diameters of bowel ends
- sutures on the larger lumen side can be spaced farther apart than those of the smaller side (for mild cases)
- intestine with the smaller lumen can be transected at an angle
- spatulated
- lumen diameter of the larger segment can also be reduced
Stapled anastomotic techniques include (4):
- everting, triangulating end-to-end anastomosis (EEA) with a thoracoabdominal (TA) 30 stapler;
- inverting end-to-end anastomosis with an EEA stapler;
- side-to-side (functional end-to-end) anastomosis using the gastrointestinal anastomosis (GIA) stapler.
- Skin staplers have been used experimentally in dogs
open lumen, functional end-to-end GIA technique
- easy, requires few staple cartridges, does not compromise the anastomotic lumen, and can be performed rapidly
- luminal disparity is not an issue
- A TA 55 (3.5-4.8mm) is placed across the intestinal edges
- Partially offsetting the GIA staple lines (so they are not on top of one another) before applying the TA stapler could provide greater protection against suture line leakage
- anchoring suture is placed at the base (crotch) of the GIA staple line to prevent tension and separation
modification: GIA stapler, rather than the TA stapler, is used to perform the final closure of the enterectomy
Where is a stapled anastomosis most likely to fail?
What are some recommendations to reduce this risk?
Along the TA staple line, particularly in area where the TA and GIA staple lines overlap
Recommondations:
Partially offsetting GIA staple lines before applying the TA stapler
Omental patch
Serosal patch
advantages and disadvantages of mechanical stapling over hand-sewn
- decreased surgery time
- minimized bowel manipulation
- similar luminal diameter, which is not a concern with these GIA-based stapling techniques
disadvantages
- large size of the GIA instrument,
- extra care required when using the GIA devices in distal jejunum-to-ileum anastomosis
Enterotomy and Intestinal Biopsy
- enterotomy: longitudinal incision is made in the antimesenteric border of the bowel immediately aboral to the foreign object. This ensures that the suture line is placed in healthy bowel that has not undergone pressure necrosis or distention
biopsy
- If longitudinal closure of the defect compromises the lumen, the defect can be closed transversely
- stay suture is placed, a full-thickness wedge of tissue is removed
- 6-mm skin punch biopsy instrument
enteroplication
- to decrease the recurrence rate of intussusception.
- Complete plication of the jejunum and ileum has been recommended by some authors because intussusception tends to recur at sites away from the initial lesion
What are potential complications of enteroplication (7)?
Obstruction
Perforation
Strangulation
Generalised ileus
Septic peritonitis
Intrabadominal abscess formation
Localised midjejunal volvulus
Complications can occur immediately or weeks to months after surgery. One study has shown that the rate of complication with enteroplication was higher than the rate of recurrence of intussusceptions treated without enteroplication
post op complications
- septic peritonitis (6%)
- adhesions
- short bowel
- ileus
septic peritonitis
- dehiscence rate 7% to 16%
- full-thickness biopsy up to 11%
- risk factors: Hypoalbuminemia, hypotension, blood products, long bowel resected, delayed enteral feeding +/- foreign body
- preoperative septic peritonitis important risk factor: developed in 38% of dogs with preoperative peritonitis, only 6% of dogs without
- signs occur between 2 and 5 days
- increase in the band neutrophil count may be more suggestive
- centesis: presence of many intracellular or extracellular bacteria, plant material or other foreign fibers, or huge numbers of degenerate neutrophils
- peritoneal fluid must be interpreted cautiously and considered in light of the patient’s clinical signs, hemodynamic parameters, and blood test results
- broad-spectrum intravenous antibiotics, fluids, inotropic and pressor drugs, plasma
- site of dehiscence is surgically repaired or resected and supported with a serosal or omental patch
- thoroughly lavaged and drained
- closed suction drains: 75-86% survival, risk for contamination and nosocomial infection,
- open drainage
- closed abdomen
- Hypoproteinemia and hypoalbuminemia are common complications of drainage
List some of the difficulties in diagnosing post-operative septic peritonitis
Ultrasonographic appearance of healthy post-op enterotomy and dehiscense can be similar (echogenic effusion and the presence of fluid adjacent to the surgical site, changes in bowel wall layering)
Comparison of peritoneal and periphral glucose and lactate is not reliable in post-op abdomens
Peritoneal fluid from closed suction drains in nonseptic dogs after laparotomy can have intracellular and extracellular bacteria for up to 1 week post-op
nondegenerate neutrophils predominate in peritoneal lavage fluid for at least 3 days after uncomplicated intestinal anastomosis
What is the prognosis for septic peritonitis?
Prognosis with use of post-op closed suction drains?
Approx 50% survive
(Reported mortality rates range from 15-85%)
Closed suction drains survival 73-85%
Adhesions
- active fibrinolytic system that usually prevents adhesion formation after laparotomy.
- occur when disruption of the equilibrium between normal fibrin deposition and fibrinolysis.
- Factors disrupt equilibrium: ischemia, hemorrhage, foreign body, and infection
- minimize adhesion: atraumatic tissue handling, moistening of tissues, and strict asepsis
- intestinal obstruction can be caused by postoperative adhesions
- A single irrigation with normal saline just before closure of the laparotomy incision does not reduce adhesion formation
Short-Bowel Syndrome
- characterized by malabsorption and malnutrition
- due to reduced mucosal surface area, gastric and intestinal hypersecretion, bacterial overgrowth, and decreased intestinal transit time
- Persistent watery diarrhea with progressive weight loss
treatment
- Meals should be small, frequent (six to eight per day), and highly digestible
- Fiber (10% to 15% on a dry matter basis)
- Animals may require injections of fat-soluble vitamins until diarrhea resolves
- antidiarrheal drugs such as loperamide
- Bacterial overgrowth can be treated with amoxicillin, tetracycline, metronidazole
- may take several weeks to months
prognosis
- ~50% removed, 80% good outcomes (many still soft and foul-smelling stools)
- chronic diarrhea, weight loss, and dehydration > euth
- individual
Contrast agent, per os, reaches the colon within 5 to 12 minutes
What percentage of the bowel resection will result in short bowel syndrome in some dogs? Is distal or proximal resection better tolerated?
Resection of 50% of the bowel can result in short bowel syndrome (some have recovered well from 85%…)
Proximal resection is better tolerated
Ileus
- common
- caused by overactivity of the sympathetic nervous system
- Diffuse intestinal dysmotility during functional or mechanical ileus can result in intestinal dilation, increased intraluminal pressure, and bacterial translocation
- exacerbated by opioid
- Treatment of ileus includes correction of any underlying disorders
- Early postoperative ambulation and feeding
- Metoclopramide (1 to 2 mg/kg/d) is a prokinetic drug that increases duodenal and jejunal peristalsis and amplitude and tone of gastric contractions and decreases pyloric sphincter tone and duration of gastric emptying and intestinal transit
Intestinal Foreign Bodies
- Approximately two-thirds lodge in the small intestines, particularly the jejunum, compared with other digestive tract locations
- results in partial or complete intestinal luminal obstruction, tissue necrosis, intestinal perforation
- obstruction results in dysmotility; excessive intraluminal fluid; malabsorption of water and solute, fluid, electrolyte, and acid–base disturbances; and proliferation and translocation of luminal bacteria
FB - Dx
- up to 50% of cats, the linear foreign body is attached around the base of the tongue
- radiographic sign of mechanical obstruction is the presence of multiple loops of gas-dilated small intestine
- up to 30% of obstructed dogs do not have radiographic signs
- inear foreign bodies, the small bowel appears plicated
- Contrast radiography can also be used to provide a definitive diagnosis of intestinal obstruction
- Abdominal ultrasonography has greater accuracy, fewer equivocal results, and provide better diagnostic confidence (97%) for identifying small intestinal obstruction compared with radiography (limitations are gas and experience)
What are the reported radiographic ratios for assessing small intestinal dilation?
false-positive and false-negative diagnoses are possible
Dogs - intestinal diameter to the height of L5 body at narrowest point. Ratios <1.6 are unlikely to be obstructed whereas ratios >2 are highly likely to be obstructed. Sensitivity and specificity of 66%
Cats - Comparing the maximal SI diameter to the height of the L2 cranial end plate. Ratios <2 are likely non-onstructive, ratios >3 have a higer liklihood of obstruction
What percentage of stable, healthy cats with a linear FB anchoured under the tongue can be successfully managed conservatively?
47%
This is not considered a good option for dogs as 40% have peritonitis at the time of surgery and their overall prognosis is more guarded with 30% having gross contamination at time of surgery and 40% requiring resection and anastomosis
FB surgery
- bowel healthy, the object is removed through a longitudinal, antimesenteric enterotomy aboral to the obstruction.
- bowel wall is necrotic, resected, and an end-to-end anastomosis is performed.
- partially obstructive foreign body may pass into the large intestine
- linear foreign body can be removed by using a single enterotomy catheter technique (The catheter is then milked aborally through the intestines and out to the anal orifice, carrying the foreign body with it) or through multiple enterotomies
- perforations of the mesenteric border of the plicated bowel may not become apparent until the tension on the string is released
- areas of questionable viability throughout the entire length of the bowel > second celiotomy can be planned 24 hours later (rather than short bowel risk)
FB Px
- Mortality rates of 1% to 8% are reported following surgical treatment, with financial concerns and sepsis commonly cited as factors contributing to euthanasia and death
- linear FB in dogs more guaraded > more often have intestinal perforations, and more than 40% require intestinal resection and anastomosis
- Intestinal perforations, which are uncommon in cats, are more likely to be associated with death after surgery
Intestinal Incarceration and Strangulation
- Entrapment usually occurs within traumatic body wall hernias; however, entrapments in omental tears, congenital hernias, or mesenteric rents
- intestinal lumen may become constricted> incarceration can rapidly progress to strangulation with subsequent intestinal ischemia and septic or endotoxic shock (bacterial translocation)
- Surgery should not be delayed if strangulation or necrosis is suspected. If herniated intestines are necrotic, resection and anastomosis may be necessary
What is pseudo-obstruction?
What is the prognosis?
Ineffective aboral intestinal propulsion, resulting in clinical and radiographic signs of obstruction in the absence of an occluding lesion
Prognosis is grave with euthanaisa usually opted for due to chronicity and recurrence of signs despite attempted treatment (Usually non-responsive to medical management for ileus, if focal resection and anastomosis may be temporarily palliative, antibiotics may help with bacterial overgrowth)
Intussusception
- Affected animals are often younger than 1 year of age
- cylindrical mass in the cranial to midabdomen is often palpable.
- ultrasonography an intussusception appears as a series of concentric rings in the transverse image or parallel lines in a longitudinal image
- surgical reduction or resection is usually required
- multiple intussusceptions can occur simultaneously
- Enteroplication, particularly if generalized enteritis is present (contraversial)
- Spontaneous reduction of intestinal intussusception has been reported in young dogs
- should be tested and treated for endoparasites
- Intussusceptions often reoccur at a site proximal to the initial
List some potential causes of intussusception?
Parasites
Virus
Linear FB
Caecal inversion
Previous abdominal Sx
Post-parturient queen
Intestinal neplasia
What is the reported recurrence rate for intussusception?
What is ther reported success rate of laparoscopic assisted pneumatic reduction of ileocolic intussusceptions?
6-27%
Can occur within 3d or up to 3wk post-op
Laparoscopic assisted - successful in 26/27 dog with average time of 2.5-4.0 minutes. Perforation occured in 1 dog and recurrence in another
Mesenteric Volvulus
- rare and often fatal condition in which the bowel twists on its mesenteric axis, resulting in strangulating mechanical obstruction and ischemia of the small intestines
- cause of mesenteric volvulus is unknown; enteritis,carcinoma, foreign bodies, surgery, blunt trauma, GDV
- peracute to acute, with rapidly progressive abdominal distention and hematochezia
- ddx GDV
- The uniform and extensive nature of the small intestine distention and normal position of the stomach differentiate to FB
- Unfortunately, by the time the diagnosis, most of the intestinal tract is ischemic and necrotic, and the animals often die or must be euthanized
- reperfusion injury with derotation
- duodenoileal anastomosis was performed without derotation
- If the torsion is segmental, resection and anastomosis can have a good prognosis.
What breeds are predisposed to mesenteric torsion?
What portions of the intestines are effected?
GSD
English Pointers
Ischaemic necrosis of distal duodenum, jejunum, ileum, caecum, ascending colon, and proximal descending colon
trauma
- bite wounds, gunshot injuries, and motor vehicle impact.
- mesentery of a segment of jejunum can become avulsed at the mesenteric border of the small intestine
- may lead to development of septic peritonitis
- Blunt probing of the wound can also be inaccurate; the sensitivity for diagnosis of peritoneal penetration was only 60% in one study
- abdominocentesis may help ID perforation
What are the most common forms of intestinal neoplasia?
annular or expansile mass lesions
Adenocarcinoma
Lymphoma (most common in cats 55%) - solitary or part of multicentric dz
Mesenchymal tumours (GIST, GIST-like, leiomyoma, leiomyosarcoma)
Non-neoplastic inflammatory lesions can mimic neoplasia including haematomas, abscess, progranuloma and sclerosis
neoplasia
- Ultrasonography is a sensitive diagnostic test for identifying mass lesions and other neoplastic changes
- acilitates evaluation of regional lymph nodes and other abdominal organs
- Cytology can help differentiate between tumor types
- Thoracic radiographs should be performed in all dogs and cats with intestinal tumor
- En bloc resection is performed to include the affected bowel, at least 3 cm of grossly normal bowel in each direction, and a similar margin of mesentery
- Small intestine resection and anastomosis has been successfully performed in cats with alimentary lymphoma and is associated with good short-term outcomes > long term outcome beneft is less known, unsure if has place in tx
- Adjuvant chemotherapy is often recommended following resection of solid neoplastic intestinal masses; however, few studies of any kind exist to support benefit
prognosis
- carcinomas, lymph node metastasis is associated with poorer prognosis,
- Dogs with completely excised intestinal smooth muscle tumors can experience long-term tumor control, with up to 67% experiencing 2 years
What is the prognosis for GI lymphoma in cats?
In dogs?
Cats - Small cell lymphoma has a better prognosis than large cell but response to treatment is the most importatn prognostic factor.
Small cell lymphoma MST 22-25m
Large cell lymphoma MST 5-7m
Dogs have a poor prognosis with GI lymphoma with survival times days - weeks regardless of treatment. MST 14d
Lymphoma is typically treated medically, with CHOP (cyclophosphamide, hydroxydaunomycin [doxorubicin], Oncovin [vincristine],and prednisolone)-based chemotherapy in dogs and in cats with large cell tumors
What is Feline Gastrointestinal Eosinophilic Sclerosing Fibroplasia (FGESF)?
What breeds are predisposed?
What are the most common sites?
What is the treatment?
Nodular, proliferative, eosinophilic inflammatroy lesion associated with GIT and alimentary lymph nodes
Intralesional bacteria are identified in up to 70% of cases, and most cats also have a peripheral eosinophilia
Persians and Siamese
Most commonly gastroduodenal and ileocolic regions
Surgical excision and prednisolone therapy
histo: eosinophilic inflammation,reactive fibroblasts, dense collagen
What paraneoplastic syndromes can be seen with GI neoplasia?
Hypereosinophilia (T-cell lymphoma)
Hypoglycaemia and nephrogenic DI (dogs with smooth muscle tumours)
What is the reported mortality rate of GI FB obstruction?
1-8%
Congenital Malformations
- intestinal diverticula and duplication
Performance time and leak pressure of hand-sewn
and skin staple intestinal anastomoses and enterotomies
in cadaveric cats
Miller 2024
Study design: Ex vivo, randomized study.
Animals: Fresh feline cadavers (n = 20).
Conclusions: HSA construct completion took twice as long as SSA with no
difference in intraluminal pressures. Although HSE construct completion took
8x as long as SSE, HSE had higher intraluminal pressures.
Clinical significance: In cats, SSA may be an alternative to HSA for intestinal
anastomosis, but SSE is not recommended as an alternative to HSE for intestinal
enterotomy closure.
leakage occurred in the center of the closure in 40% of SSA compared to only 15% of HSA.
SSE also had quicker construct times but had
decreased intraluminal pressures compared to HSE. In
addition,15 immediate leakage in over one-third of constructs
was very concerning for use in live cats. Therefore,
the authors do not recommend SSE in live cats
Some degree of mucosal eversion is reported with both SSA and HSA techniques10; however, different amounts may be present and it is unknown how much
this affects healing of the individual techniques. With eversion, mucosal ischemia and necrosis occurs and may
result in delayed secondary healing instead of primary appositional healing.18 Everted intestinal anastomoses
have also been reported to have lower bursting strengths during the healing lag phase and increased risks for leakage18;
STUDY: Clinical relevance: Cadaveric feline intestine cooled for up to 29 h may be
used for determining intestinal leak pressures.
STUDY: Freezing and subsequent thawing prior to specimen testing reduced
ILP compared with use of fresh and chilled specimens but did not affect MIP
among experimental groups.
Clinical significance: Cadaveric canine intestinal specimens tested immediately after
collection or after chilling for 24 hours should be recommended
STUDY: staples used successfully clinically in cats
In a canine retrospective study of 210 R&As,
intraluminal stapling techniques were found to have less
dehiscence (9.7%) than hand-sewn (28.9%) anastomosis
techniques when PSP was present.5 However, when PSP
was not present, there was no difference in dehiscence
between intraluminal stapling (4.2%) and hand-sewn
(8.2%) anastomosis techniques,5
Gastrointestinal thickness, duration, and leak pressure
of five intestinal anastomosis techniques in cats
Sanders 2024
(1) hand-sewn anastomosis – simple interrupted (HSA-SI),
(2) hand-sewn anastomosis – simple continuous (HSA-SC),
(3) functional end-to-end stapled
anastomosis (FEESA),
(4) functional end-to-end stapled anastomosis with oversew (FEESA-O),
(5) skin stapled anastomosis (SS).
there was no difference in Initial Leak P or Max Intralumunial P
All anastomosis techniques provide resistance to leakage that is
supraphysiological to that of the normal maximum intraluminal pressure.
HSA take longer to complete than stapled anastomoses
The transverse staple line has repeatedly been implicated
as the most common site of leakage and abscessation in
FEESA constructs; thus, it stands to reason that reinforcement
with suture would fortify the inherent weakness
of this site.9,14,16,18 However, in our study, no
statistical difference was found
studied the thickness of feline gastrointestinal
tissue in cadaveric tissue for the purpose of facilitation
of correct staple size selection:
pertinent to select green TA staples
green (2.0 mm closed staple height) for use in the duodenum,
jejunum, and ileum, whereas it may be more
appropriate to select blue TA staple cartridges (1.5-mm
closed staple height) for use on the feline stomach.
tan Endo GIA cartridges (recommended
for tissue thickness ranging from 0.88 to 1.8 mm) is
appropriate in the feline stomach. The remainder of the
feline gastrointestinal tract has mean thicknesses very
near to the purple/black GIA cartridge selection size distinction
of 2.25 mm
However, a study performed
in healthy, nonanesthetized dogs showed maximum
intraluminal pressures induced by peristalsis to be
between 15 and 25 mmHg
Effects of cyanoacrylate on leakage pressures of cooled
canine cadaveric jejunal enterotomies
Thompson 2024
Conclusion: Reinforcement of a sutured enterotomy closure with cyanoacrylate
was easy to perform and resulted in significantly increased initial leak
pressures in cadaveric jejunum.
synthetic sealants may have the potential
to decrease postoperative intestinal leakage or dehiscence
Clinicopathological findings, treatment, and outcome in 60 cats
with gastrointestinal eosinophilic sclerosing fibroplasia
Cerná 2024
retrosepctive
30% were
Domestic Shorthairs and 12% were Domestic Longhair cats, with the most prevalent
pedigree breeds being Ragdolls (25%)
Eosinophilia was present
in 50% and hypoalbuminemia in 28% of cats. The mass was removed surgically
in 37% of cases. Most cats (98%) were treated with corticosteroids. Survival was not
statistically different between cats treated with surgical resection and cats treated
with medical therapy alone, 88% of the cats were still alive at the time of writing
The indication to follow surgery with corticosteroid
therapy is further supported by 13 cats where prednisolone
was discontinued, 85% of these had to have prednisolone restarted a
median of 114 days after discontinuation because of recurrence of
clinical signs.
The indication to follow surgery with corticosteroid
therapy is further supported by 13 cats where prednisolone
was discontinued, 85% of these had to have prednisolone restarted a
median of 114 days after discontinuation because of recurrence of
clinical signs.
Endoscopic and surgical treatment of non-neoplastic proximal duodenal ulceration in dogs, and anatomical study of proximal duodenal vascularisation
M. C. Sabetti 2023
A submucosal vascular network was evident in all the casts, with a prominent venous plexus seen exclusively in the first half inch of the duodenum. In clinical cases, on endoscopic examination, the duodenal ulcer was located at the proximal part of the duodenum, involving the mesenteric portion of the wall. The dogs not responding to medical treatment (6/12) were treated with endoscopic electrocauterisation, surgical coagulation or resection
Association of mesenteric volvulus
in police working dogs with and without
a prior prophylactic laparoscopic gastropexy
Fruehwald
370 PWDs (82 with and 288 without PLG).
Prophylactic gastropexy may be associated with an increased risk for MV. However, patients without prophylactic gastropexy are at risk for gastric dilatation and volvulus, which is more common than MV. Therefore, the authors continue to recommend prophylactic gastropexy to decrease the risk for gastric dilatation and volvulus.
Intestinal full-thickness needle-core biopsy
via laparotomy is safe, rapid, and effective and less invasive than standard incisional biopsy in dogs and cats
Maggiar 2024
3 dogs and 17 cats
There were no complications associated with the needle-core biopsy. The diagnoses resulting from both techniques were 100% concordant for the distinction between inflammatory bowel disease and intestinal lymphoma
Comparison of a simple continuous versus simple
interrupted suture pattern for the repair of a large, open duodenal defect with a jejunal serosal patch in a canine cadaveric model
Lorange 2020
20 constructs were created through repair of large, open duodenal defects with circumferential suturing of an intact jejunal segment (jejunal serosal patch). Constructs were randomly assigned to have the serosal patch anastomosed to the duodenal segment by a simple continuous or simple interrupted suture pattern.
Jejunal serosal patches adequately sealed large, open duodenal defects and prevented leakage in these constructs. Constructs with simple continuous or simple interrupted suture patterns withstood physiologic and supraphysiologic intraluminal pressures, although constructs with a simple interrupted suture pattern initially leaked at higher pressures
cautioned before in vivo testing has been demonstrated to yield successful outcomes.
Retrospective evaluation of surgical
treatment of linear and discrete
gastrointestinal foreign bodies
in cats: 2009–2021
Gollnick 2023
A total of 56 cats were included in this study; 38 cats had a DFB and 18 had an LFB. No cats developed
postoperative septic peritonitis, and all cats survived. The likelihood of postoperative septic peritonitis or mortality
in an additional cat was estimated to be <5.2%.
Cats undergoing surgery for gastrointestinal FBs had a low incidence of postoperative
complications. Cats with LFBs had longer surgeries and were more likely to develop postoperative SSIs (43%)
lack of significant increase in diagnostic accuracy using
follow-up radiographs in cases of occult gastrointestinal mechanical obstruction, other diagnostic
options (eg, abdominal ultrasonography) could be considered when survey abdominal radiographs
are inconclusive for the diagnosis of mechanical obstruction in dogs and cats.
Gastrointestinal signs and a need for nutritional
management may persist long term in dogs and
cats undergoing resection of the ileocolic junction:
35 cases (2008–2020)
Stecyk 2022
20 dogs and 15 cats that underwent ICJ resection
Ten of 20 dogs
(50%) and 11/15 cats (73%) were reported by their owners to have a good long-term outcome based on the lack
of long-term gastrointestinal sign
CLINICAL RELEVANCE
Owners should be informed of the possibility of long-term gastrointestinal clinical signs and the potential need for long-term nutritional management after ICJ resection.
A quantitative evaluation of the effect of foreign body
obstruction and enterectomy technique on canine small
intestinal microvascular health
Kaitlyn M. Mullen 2023
Objective: To investigate sidestream dark field (SDF) videomicroscopy as an
objective measure of intestinal viability and determine the effects of enterectomy
techniques on intestinal microvasculature in dogs with foreign body obstructions.
Study design: Prospective, randomized, clinical trial.
Animals: A total of 24 dogs with an intestinal foreign body obstruction and
30 systemically healthy dogs.
Sidestream dark field videomicroscopy can identify obstructed
intestine and quantitate the severity of microvascular compromise. Handsewn
and stapled enterectomies equally preserve perfusion.
Clinical significance: Stapled enterectomies do not lead to greater vascular
compromise than handsewn enterectomies.
Thus, the increased morbidity
associated with foreign body obstructions may be primarily
attributed to the surgeon’s inaccurate subjective
assessment of intestinal viability.
Clinical outcomes of the use of unidirectional barbed
sutures in gastrointestinal surgery for dogs and cats:
A retrospective study
Eric Monnet 2024
Sample population: Twenty-six client-owned dogs; three client-owned cats
Six gastrotomies, 21 enterotomies, and nine enterectomies
None of the cases in the study developed leakage, dehiscence,
or septic peritonitis during the 14-day short-term follow up.
Two dogs had intestinal obstruction
due to strictures at the surgical site (11%)
including leukocyte
infiltration into tissue and abscessation leading to luminal narrowing
Further investigation of
the role of unidirectional barbed sutures leading to abscess, fibrosis, or stricture
is necessary
Intestinal dehiscence and mortality
in cats undergoing gastrointestinal
surgery
Hiebert 2021
In this population, the rate of dehiscence of GI incisions in
cats was exceedingly low (0.8%) but not absent. Likewise,
patient mortality was higher than expected at 18.2%. PSP was associated with decreased patient survival,
23 died, nine died spontaneously
and 14 were euthanized. Date of death ranged from the day of surgery to 9 days (median 3) postoperatively.
Eighteen cats died while hospitalized and
five died following hospital discharge
Influence of crotch suture augmentation on leakage
pressure and leakage location during functional end-to-end
stapled anastomoses in dogs
Duffy 2022
randomized, experimental.
Sample population: Chilled jejunal segments from 3 adult dogs
(1) no crotch suture (NCS); (2) simple interrupted crotch
suture (SICS); (3) two simple interrupted crotch sutures (TCS) placed laterally
on opposing jejunal limbs; (4) simple continuous crotch suture (SCCS) augmentation.
Augmenting the FEESA with crotch suture(s)
improved the resistance of the jejunal anastomosis to leakage in normal cadaveric
segments. Placing 2 crotch sutures or use of a simple continuous pattern
for anastomotic augmentation appeared to be superior to the placement of a
single suture.
Received: 28 June 2021 Revised: 5 November 2021 Accepted: 18 December 2021
DOI: 10.1111/vsu.13764
Veterinary
Intraoperative surgeon probe inspection compared to leak
testing for detecting gaps in canine jejunal continuous
anastomoses: A cadaveric study
Culbertson 2021
Dehiscence rates after intestinal anastomoses in dogs can be high (5%–28%)5–11 and often are fatal, with mortality rates ranging between 25% and 85%.
Experimental study.
Animals: Normal jejunal segments (n = 24) from two fresh canine cadavers.
Nineteen out of twenty-four (79.2%) samples had at least one probe
drop, and four out of twenty-three (17.4%) samples leaked
intraoperatively. PT
did not identify the IG quadrant in 3/16 (20%) samples,
which means this method also missed some 4 mm gaps.
PT was highly sensitive at detecting gaps compared with LT
The diagnostic value of PT appears adequate to recognize
gaps in cadaveric small intestinal anastomoses. PT offers surgeons an
alternative to detect suture gaps
probing with fine mosquito hemostat
Evaluation of intraoperative leak testing of small intestinal
anastomoses performed by hand-sewn and stapled
techniques in dogs: 131 cases (2008–2019)
Mullen 2021
Performance of intraoperative anastomotic leak testing, regardless of
the anastomotic technique, was not associated with a reduction in the
incidence of postoperative anastomotic dehiscence
potential usefulness of intraoperative
anastomotic leak testing in improving surgical
technique, the authors believe intraoperative anastomotic
leak testing may have the greatest clinical usefulness
for novice surgeons in helping eliminate poor
surgical technique as a factor for dehiscence
At present, there is only
one veterinary study comparing intraoperative testing
results to postoperative dehiscence rates.41 In this retrospective
study, Mullen et al compared 144 anastomoses to
13 cases of postoperative dehiscence; they found no significant
difference in dehiscence rate in tested versus untested
segments or those tested positive versus negative.41
Ex vivo comparison of leak testing of canine jejunal
enterotomies: Saline infusion versus air insufflation
Kaitlyn M. Mullen 2021
enterotomy closures leak at lower pressure (ILP 68.5mmHg) with air injection
- max intraluminal pressure 78.3mmHg
- air insufflation may be more sensitive and easier to identify (bubbles in saline filled abdo)
is leaking through the suture tract significant? Cannot correct this by placing additional sutures..
Comparison of patient outcomes following enterotomy
versus intestinal resection and anastomosis
for treatment of intestinal foreign bodies in dogs
Daniel J. Lopez 2021
Dehiscence rates were 3.8% (7/183) and 18.2% (8/44) for enterotomy and IRA,
respectively
Patients undergoing IRA were at a significantly higher risk of intestinal dehiscence,
compared with patients undergoing enterotomy
Ex vivo comparison of leakage pressures and leakage
location with a novel technique for creation of functional
side-to-side canine small intestinal anastomoses
Kyle L. Chu
ability of functional side-to-side small intestinal
anastomoses (FSS-SIA) created with an electrothermal bipolar vessel sealing
(EBVS) device to resist leakage
Clinical findings and outcomes of 153 dogs surgically
treated for intestinal intussusceptions
Larose 2020
median age 10m, ileocolic most common (43%), most no identifiable cause (67%)
- 29/153 (19%) surgical procedure within 30 days of intussusception
- resection anastomosis in 84%; enteroplication in 18%
- intra-op complications: 7% - 7/7 intestinal damage during reduction
- post-op complications: 35%, 14% life-threatening
- 2.6% recurrence (4/4 within 72 hour post-op) – 2/4 had partial enteroplication
- 14 day mortality rate 6%
According to two reports of previous retro
spective studies, EP did not influence recurrence rates.
EP dd not result in any complication other than recurrence
Influence of oversewing the transverse staple line
during functional end-to-end stapled intestinal
anastomoses in dogs
Duffy 2020
FEESA alone, FEESA + Cushing oversew, or FEESA +
simple-continuous oversew of the transverse staple line with 3-0 polydioxanone.
Our results provide evidence to support oversewing the
transverse staple line after FEESA. Doing so may reduce the occurrence of
postoperative dehiscence. These findings warrant additional focused investigation
in vivo through a prospective randomized clinical trial.
Rates of anastomotic leakage in dogs after FEESA range from 0% to 13%,8-10 with high mortality rates of 74% to 85%.
Reported advantages of FEESA compared with
hand-sewn techniques include decreased surgical time,
preservation of intestinal blood supply, reduced soft
tissue handling and manipulation of the bowel, ability
to deal with luminal disparity, consistency of staple
placement, higher wound tensile strength during the
late inflammatory phases of intestinal healing, and
decreased inflammation and necrosis.2-7
Sumner 2019
Study design: Retrospective observational study.
Sample population: Seventy-seven client-owned dogs that underwent 78 FEESA
reinforced (n = 30) or not reinforced (n = 48) with suture at the transverse staple line.
Oversewing the transverse staple line in FEESA was associated with
a reduced occurrence of postoperative dehiscence.
Outcomes in 40 cats with discrete intermediate- or large-cell
gastrointestinal lymphoma masses treated with surgical mass
resection (2005-2015)
Tidd 2019
- 23/40 SI, 9/40 LI, 8/40 gastric
- 36/40 (90%) survival to discharge, 31/40 alive at suture removal
- survival to suture removal → MST 185d
- large intestinal mass (colon)→ longer survival (MST 675) vs SI (64d), gastric (96d)
- complete excision → longer survival (MST 370d vs 83)
- adjuvant therapy → no improvement in survival
Most cats in this population survived the perioperative period, with
MST similar to those reported historically with medical management
protocols. Unlike in dogs, in which multicentric LSA predominates
and is overwhelmingly responsive to chemotherapy,
the response to multiagent chemotherapy in cats with feline GI
large-cell LSA is less predictable, with overall response rates
ranging from 30% to 75%.4-11 Response durability also tends to
be less favorable, with reported median survival times (MST) of
3 to 6 months.
Effects of needle gauge and syringe size on small intestinal
leakage at injection sites
Kenneth J. Brand 2019
22-G needle reduced frequency of leakage after leak testing
- 20mL injection → higher frequency of leakage
- smaller syringe size with 22G needle may lower frequency of leakage from injection site
- influence on leak testing unknown
Intestinal incisional dehiscence rate following enterotomy
for foreign body removal in 247 dogs
Alena Strelchik
8 of the 247 (3.2%) dogs had preoperative septic peritonitis, and all 8 dogs
survived to hospital discharge. Incisional dehiscence occurred following 5 of
the 247 (2.0%) enterotomies, and only 2 dogs in the dehiscence group did
not survive to hospital discharge.
Retrospective study of survival time and prognostic factors
for dogs with small intestinal adenocarcinoma treated
by tumor excision with or without adjuvant chemotherapy
Smith 2019
- overall MST 544d; 1y survival 60%, 2y survival 36%
- px factors for survival: age only - <8y → MST 1193d vs >8y (488d
- survival not associated with LN metastasis, adjuvant chemotherapy, NSAID administration
or any other variables
Odds for dehiscence were significantly greater for sutured end-to-end
anastomoses than FEESAs, and dogs undergoing surgery for previous dehiscence
were significantly more likely to experience a subsequent dehiscence
with a sutured anastomosis. However, variability of procedure types
and dehiscence rates among clinics suggested further research is needed
to confirm these findings. Obstruction at the anastomosis site was identified
as a potential long-term complication of FEESA. ( J Am Vet Med Assoc
2018;253:437–443)
Influence of preoperative septic peritonitis and anastomotic
technique on the dehiscence of enterectomy sites in dogs:
A retrospective review of 210 anastomoses
Davis 2018
dehiscence: overall 11.4%, pre-op septic peritonitis 21.1%, no septic peritonitis 6.6%
- indication for anastomosis not associated with dehiscence
- risk factors: septic peritonitis and hand-sewn anastomosis
- stapled anastomosis less likely to dehiscence with septic peritonitis (9.7% vs 28.9%)
Linear and discrete foreign body small intestinal
obstruction outcomes, complication risk factors, and single
incision red rubber catheter technique success in cats
Miller 2024
Retrospective study.
Animals: Client-owned cats (n = 169).
RRCT was successful in 20/24 attempts of LFBO removal
Postoperatively,
two cats (DFBO) experienced intestinal dehiscence and two cats
(DFBO) died or were euthanized. Survival to discharge (p = 1.0000) and postoperative
complications (p = .1386) did not differ between LFBOs and DFBOs
Cats with LFBOs and DFBOs have similar postoperative
complication rates and survival to discharge when preoperative septic peritonitis
is not present. Intestinal dehiscence is rare, which is important when
discussing surgical prognosis with owners. A RRCT can be considered to
remove LFBOs when there is concern for multiple enterotomies.
Laparotomy-assisted endoscopic removal of gastrointestinal
foreign bodies: Evaluation of this technique and postoperative recovery in dogs and cats
Cola 2024
Retrospective observational study.
Sample population: Dogs and cats (n = 81) with gastrointestinal FBs
In 5/40 cases conversion required
Laparotomy-assisted endoscopic removal allowed complete or partial
removal of FBs in 35/40 dogs
The presence of intestinal wall damage (p = .043) was
associated with the conversion to an enterotomy. Group 1 required a shorter
postoperative hospital stay (p = .006), less need for analgesia (p < .001), and
experienced a faster resumption of spontaneous feeding (p = .012), and similar
complication rate to Group 2.
Subgroup B
included 17 cases (17/40), and at least one enterotomy
was required
the procedure started with
a celiotomy in order to assess the possibility of moving the FB into the stomach; if possible, then this was followed by endoscopic removal.
Stapled functional end-to-end intestinal anastomosis with endovascular gastrointestinal anastomosis staplers in cats and small dogs
S. Genoni 2024
Twenty-five patients (10 dogs and 15 cats) were included
Five patients developed minor postoperative complications, including three superficial surgical site infections. No major postoperative complications were reported. Eighteen patients were alive at the end of the study, one patient was lost to follow-up
Normal small intestinal diameter in
cats is reported to be less than 12 mm
Endovascular GIA staplers are smaller devices compared to
standard GIA staplers
Stapled anastomoses in this study were performed with 45-to 60-mm long endovascular-GIA
staplers and this length was deemed
safe given that no major complications were encountered.
60-mm
long stapler jaw might
be unnecessary in small dogs and cats and could lead to an
excessively long anastomotic site that may impact peristaltic
function, resulting in accumulation of intestinal content at
the anastomosis site.
Fifteen out of 25 of our patients underwent intestinal resection
and FEESA using an open lumen technique, whereas 10 of 25 underwent a one-stage
technique
Stapled enterectomy reduces
surgical time when compared with
sutured enterectomy: a retrospective
review of 54 cats
Costello 2024
54 cats met the inclusion criteria for this study, with 24 undergoing an SFEEA while 30 underwent
EEA. There was a significant difference in surgical time between the two groups. The SFEEA group had a mean
surgical time 34.3 ± 9.274 mins faster than the EEA group (P <0.001). Unique complications reported for the SFEEA
group included haemo abdomen and anastomotic stricture.
(93%) survived to discharge with a median duration of hospitalisation of 4 days
Veterinarians were >3 times more
likely to use a surgical stapler in the presence of pre-existing
septic peritonitis.
The overall complication rate after feline enterectomy was 19.2%, with a complication rate after EEA of 14.3% and after SFEEA of 29.2%.
Major short-term complications included haemoabdomen
(n = 1), dehiscence (n = 1) and stricture (n = 2).
The rate of dehiscence for cats in
our data set undergoing SFEEA was 4.2%, whereas no cats dehisced after EEA
This is in contrast to a recent study of large intestinal full-thickness
incisions in cats that reported a higher rate of dehiscence
of 8.3%, where partial colectomy or colocolic anastomosis
were noted to be risk factors for dehiscence
Fixed staple heights mean that
if the staples are too small, the staple may fail to incorporate
the submucosa and this can result in iatrogenic
damage due to compression and local ischaemia, If the staple height is too large, the staple may not form
a leakproof seal or close vessels, leading to bleeding
