Let sleeping dogs lie: role of the omentum in the ileal pouch-anal anastomosis procedure.

A surgical aphorism has long held that the omentum is the "watchdog of the abdomen." However, detractors believe that leaving the omentum behind after colectomy precipitates later small bowel obstruction. A retrospective comparison was made between a group of 406 patients (Group I) having omentectomy with proctocolectomy and ileoanal anastomosis and a group of 239 patients (Group II) having a similar procedure without omentectomy. Follow-up in this series of 645 patients was 4.3 +/- 2.1 years (mean +/- SEM). No difference was present in the rate of partial small bowel obstruction or complete small bowel obstruction between Group I patients (32 percent partial, 12 percent complete) and Group II patients (29 percent partial, 12 percent complete; P greater than 0.1). However, a better outcome with regard to postoperative sepsis and sepsis requiring operation was apparent in Group II patients retaining the omentum (4 percent and 3 percent, respectively) than in Group I patients (10 percent and 8 percent, respectively), in whom the omentum was removed (P less than 0.01). As this experience would support, we urge surgeons to "let sleeping dogs lie" and, when possible, retain the omentum when performing colectomy or proctocolectomy.