BACKGROUND: Unanticipated massive resection after intraabdominal procedures is an increasing cause of short bowel syndrome (SBS). Our aim was to determine the frequency and potential mechanisms of postoperative SBS. STUDY DESIGN: We reviewed retrospectively the clinical course of 210 adult patients with SBS evaluated over a 20-year period. RESULTS: Fifty-two (25%) patients had postoperative SBS. The initial operations included colectomy (n=20), hysterectomy (n=8), appendectomy (n=5), gastric bypass (n=5), and other (n=14). Intestinal obstruction (n=38) was the most common reason for resection leading to SBS, either from adhesions (n=26) or volvulus (n=12). Postoperative intestinal ischemia led to resection in 14 patients. SBS occurred from 1 day postoperatively to years later, with 16 (30%) intestinal resections occurring within 1 month. Patients undergoing resection for intestinal ischemia were more likely to undergo resection during the first month than were patients with adhesions and volvulus (86% versus 4% and 25%,respectively, p < 0.05): Patients undergoing resection for ischemia and volvulus were more likely to have remnant length<60 cm compared with those with adhesions (57% and 58% versus 23%, respectively, p < 0.05). Patients undergoing resection for adhesive obstruction were more likely to undergo multiple resections. Thirty-five (67%) patients required longterm parenteral nutrition. Seven (13%) patients died, three in the early postoperative period and four from complications of SBS. CONCLUSIONS: SBS is a potential postoperative complication of intraabdominal procedures and accounts for a considerable proportion of tertiary referrals for SBS. Surgical treatment of postoperative obstruction after common surgical procedures is the most frequent cause. Preventing adhesions, avoiding technical errors, diagnosing a potentially ischemic intestine in a timely manner, and approaching the frozen abdomen cautiously are important strategies for preventing this condition.