To begin the procedure, isolate the affected area of intestines with moistened laparotomy pads. Ligate the blood vessels to
the transection sites with absorbable suture (Figure 1); ligate the arcuate branches along the mesenteric surface by taking suture bites around the vessels immediately adjacent
to the proposed transection sites. Milk luminal contents away from the area, and clamp the diseased intestines, along with
2 or 3 cm of healthy tissue, with Kelly or Carmalt forceps. Confine the luminal contents within the retained healthy intestines
by using noncrushing forceps (e.g. Doyen intestinal forceps), umbilical tape, or Penrose drain tourniquets that collapse the intestinal lumen but do not inhibit
blood flow. Alternatively, an assistant can occlude the intestinal lumen near the proposed transection sites with index and
middle fingers. Place the occluding devices at least 3 cm away from the anastomotic ends to prevent interference with suturing.
Transect the intestines adjacent to the ligated arcuate vessels. Luminal disparity can be corrected at this time by increasing
the angle of the cut on the narrower segment of intestines so that the antimesenteric border of the intestines is shorter
than the mesenteric border (Figure 2).
Place stay sutures at the mesenteric and antimesenteric borders (Figure 3) to ensure that the remaining sutures are properly spaced and to facilitate intestinal manipulation.5 Start a simple continuous suture pattern at the mesenteric border, leaving the suture end long. Take bites about 3 mm wide
and 3 mm apart, depending on the size of the intestines.2 If mucosa begins to evert, use a modified Gambee suture pattern: Pass the needle full thickness through the intestinal wall
and then back through the mucosa on the near side. Then insert the needle at the mucosa-submucosa border on the far side to
push the mucosa into the lumen, and pass the needle full thickness back out that side. Continue the pattern to the antimesenteric
surface, and tie it in a knot to prevent a purse-string effect (Figure 4). Flip over the intestines to expose the opposite surface, and continue suturing back to the initial mesenteric suture and
tie (Figures 5 & 6). Then close the mesentery with a simple continuous pattern of 4-0 absorbable suture material (Figure 7); take suture bites at the edge of the mesentery to avoid damaging the intestinal blood vessels.
Check the anastomotic site for leaks by distending the segment with sterile saline injected into the lumen while continuing
to occlude the intestinal segments distal to the site. Seal any leaks with interrupted sutures; the omentum can be tacked
over the anastomotic site by using a separate omental flap for each side.
Potential complications include dehiscence, peritonitis from leakage or necrosis, ileus, recurrence of clinical disease, or
short-bowel syndrome. Anastomotic leakage is reported in 3% of animals undergoing continuous sutured anastomosis and up to
11% of animals undergoing interrupted sutured anastomosis; leakage is more likely to be associated with anastomoses performed
for foreign body removal or resection of traumatized intestines.4,5,14 The risk for anastomotic leakage also increases in patients with preexisting peritonitis or hypoalbuminemia.4 Dehiscence and leakage can be reduced by ensuring adequate blood supply, reducing tension across the anastomotic site, and
providing adequate apposition.5
Ileus may result from chronic intestinal distention, excessive tissue handling, pain, sepsis, opioid use, or electrolyte imbalances.2 Magnesium, potassium, calcium, and fluid imbalances should be corrected, and food should be offered as soon as possible.
Prokinetics such as metoclopramide, erythromycin, and lidocaine may be useful for stimulating motility.5,15
Resecting more than 70% of the intestines may result in short-bowel syndrome, depending on the site of the resection and the
health of the remaining intestines.2,16 Maldigestion and malabsorption from reduced surface area will result in persistent watery diarrhea and weight loss. Dietary
modifications, including increasing soluble fiber content, may reduce clinical signs.2