PurposeThe aim of this study is to assess the short-term outcome of intraoperative colonic irrigation and primary anastomosis and to suggest the usefulness of the procedure when a preoperative mechanical bowel preparation is inappropriate.MethodsThis retrospective study included 38 consecutive patients (19 male patients) who underwent intraoperative colonic irrigation and primary anastomosis for left colon disease between January 2010 and December 2016. The medical records of the patients were reviewed to evaluate the patients' characteristics, operative data, and postoperative short-term outcomes.ResultsTwenty-nine patients had colorectal cancer, 7 patients had perforated diverticulitis, and the remaining 2 patients included 1 with sigmoid volvulus and 1 with a perforated colon due to focal colonic ischemia. A diverting loop ileostomy was created in 4 patients who underwent a low anterior resection. Complications occurred in 15 patients (39.5%), and the majority was superficial surgical site infections (18.4%). Anastomotic leakage occurred in one patient (2.6%) who underwent an anterior resection due sigmoid colon cancer with obstruction. No significant difference in overall postoperative complications and superficial surgical site infections between patients with obstruction and those with peritonitis were noted. No mortality occurred during the first 30 postoperative days. The median hospital stay after surgery was 15 days (range, 8–39 days).ConclusionIntraoperative colonic irrigation and primary anastomosis seem safe and feasible in selected patients. This procedure may reduce the burden of colostomy in patients requiring a left colon resection with an inappropriate preoperative mechanical bowel preparation.