To determine whether mechanical bowel preparation influences the inddence of anastomotic dehiscence following colorectal surgery, 186 patients undergoing elective left colonic or rectal resection were randomized before surgery to bowel preparation (n=89) or no bowel preparation (n=97). Surgical technique was standardized and no patient had a defunctioning colostomy. Seventeen patients were excluded (seven with preparation, ten without). Indications for surgery in the remaining 169 patients were carcinoma (133 patients), diverticular disease (my inflammatory bowel disease (six) and miscellaneous When dehiscence occurs after colonic or colorectal anastomosis there is a threefold increase in mortality ratel. The factors thought to contribute to anastornotic dehiscence include the patient's nutritional status, the site of anastomosis and the technical competence of the surgeon, in addition to local colonic factors such as peritoneal contamination and poor bowel preparation*.
Most surgeons consider efficient mechanical bowel preparation to be among the most important factors in preventing complications of colorectal surgery3q4, although a small minority believe it to be unnecessarys. A recent report6 of no anastomotic complications in a series of elective colonic resections performed without preoperative bowel preparation has undermined the traditional view. Good results have also been reported with primary left-sided anastomosis in a series of emergency colectomies in which the bowel was not mechanically prepared and in which peritonitis was sometimes present'. Although these reports are selected, it would appear that the role of bowel preparation in colonic surgery needs to be re-evaluated. If bowel preparation is shown to be unnecessary it would mean a shorter and more pleasant hospital stay for the patient and avoidance of the potential complications associated with this procedureR. A prospective randomized trial was therefore initiated to examine this issue.