ABSTRACT
Large-Colon Enterotomy Pelvic flexure enterotomy that allows evacuation of the colonic contents is a commonly performed procedure in horses with abnormalities affecting the large colon. Enterotomy procedures are also performed for removal of foreign bodies (usually in the right dorsal colon), and right ventral colon enterotomy is used to access the cecum in horses with a cecocolic intussusception.
For this procedure, the large colon is exteriorized and placed on a colon tray (Kimzey Metal Products, Woodland, CA) on the left side of the horse or caudally between the horse’s hind legs. If a colon tray is not available, the colon is best exteriorized between the horse’s hind legs. Some surgeons place the end of the laparotomy drape onto the tray to create a shelf to help support the weight of the colon. The enterotomy drape is then placed on top of the laparotomy drape and secured with towel clamps. The colon tray is angled at about 20° (Figure 29-1). A modified trash can with an ingesta strainer and a liquid outflow hose can be used to collect and evacuate the contents of the colon (Figure 29-2).1 Alternatively, the end of the tray can be positioned over a disposal system built into the surgery room (Figure 29-3). In anticipation of colonic evacuation, a lavage system should be established. This can be done by using two garden hoses, or one hose with a Y connection. One hose is used for intraluminal lavage and evacuation of the contents, and the other for extraluminal lavage, using warm water (37°C, 98.6°F) or a warm balanced electrolyte solution.1 If these are not available, stomach tubes, buckets, and pumps can be used.
A full-thickness 8-to 12-cm incision is made on the antimesenteric border of the pelvic flexure.2 One hose is inserted and gently advanced into the colon, while the other is used to continuously lavage the serosal surface to reduce fecal contamination (Figure 29-1). During the evacuation procedure, it is useful to lift the colon and ensure that the underside is lavaged as well. A sterile assistant helps to feed the hose into the colon and massage its contents. Although a modified colon tray has been described for evacuating the colon, it is not deemed necessary by most surgeons.3 If colonic evacuation is performed as part of the correction of a large-colon volvulus, an intestinal biopsy can be collected to evaluate the severity of damage at the time of surgery. Closure of pelvic flexure enterotomies is performed using 2-0 absorbable suture material in two layers: a simple continuous seromuscular layer followed by a Lembert or a Cushing pattern.4 The colon is rinsed with sterile saline or lactated Ringer’s solution and replaced in the abdomen.
