Early Postoperative Small Bowel Obstruction is an Independent Risk Factor for Subsequent Adhesive Small Bowel Obstruction in Patients Undergoing Open Colectomy

This prospective study was performed to investigate whether postoperative ileus (POI) or early postoperative small bowel obstruction (EPSBO) affects the development of adhesive small bowel obstruction (SBO) in patients undergoing colectomy. We prospectively enrolled 1,002 patients who underwent open colectomy by a single surgeon. POI was defined as the absence of bowel function for more than 5 days or as a delay in oral intake beyond 7 days postoperatively. EPSBO was defined as the clinical and radiologic identification of SBO after resuming oral intake between postoperative days 7 and 30. Adhesive SBO was defined as SBO developing after 30 days because of intraperitoneal adhesion. The associations between POI, EPSBO, patient- and surgery-related variables, and the development of adhesive SBO were analyzed. A total of 85 (8.5 %) patients developed POI, and 42 patients (4.2 %) developed EPSBO, with seven patients experiencing both POI and EPSBO. During the follow-up period (median 51 months), 70 patients (7.0 %) developed adhesive SBO, six (8.6 %) of whom needed laparotomy. The occurrence of adhesive SBO was significantly higher in patients with EPSBO than in those without EPSBO (26.5 vs. 7.5 % at 5 years, P < 0.001), but not in patients with POI (13.4 vs. 7.8 % at 5 years, P = 0.158). Multivariable analysis showed colostomy (hazard ratio [HR] 2.530, P = 0.006) and EPSBO (HR 4.063, P < 0.001) as independent risk factors for adhesive SBO. The development of adhesive SBO after colectomy is more frequent in patients with EPSBO and colostomy; however, POI does not increase the risk of adhesive SBO.