Colonic perforation after endoclip placement for delayed post–endoscopic-resection bleeding

A 38-year-old man with multiple colonic polyps was referred to our hospital for a polypectomy. The patient was prepared for a colonoscopy by ingestion of a 2-L polyethylene glycol electrolyte lavage solution. The colonoscopy revealed 3 polyps in the ascending colon. One of the polyps was located near the ileocecal valve; the polyp was sessile and 15 mm in diameter. Another 2 polyps were located near the hepatic flexure; these polyps were both sessile and 8 mm (Fig. 1) and 6 mm in diameter, respectively. An ER was attempted for all 3 polyps by injecting normal saline solution beneath the polyps. A needle forceps (NM-201L0423; Olympus Co, Ltd, Tokyo, Japan) was used for the saline solution injection. For excision, the polyp, together with a portion of surrounding nonneoplastic mucosa, was then grasped with a snare (SD-9U-1; Olympus). An electrosurgical generator (PSD-20; Olympus) was set at 25 W, with a pure-cutting current. After the ER, prophylactic endoclip placement was performed only for the post-ER ulcers associated with the polyp that measured 6 mm in diameter near the hepatic flexure. The next day, the patient complained of hematochezia. A colonoscopy was performed after preparation of the colon. The colonoscopy revealed bleeding from 2 of the post-ER ulcers without prophylactic endoclip placement. Hemostasis for the post-ER bleeding near the ileocecal valve was achieved by using a rotatable clip device (HX-6UR-1; Olympus) and 5 endoclips (HX-600-135; Olympus). Hemostasis was also successful by using the same device and 7 endoclips for the post-ER bleeding near the hepatic flexure (Fig. 2). The patient did not complain of abdominal pain during or immediately after hemostasis; no complications, eg, perforation, were identified during the colonoscopy. Three hours after hemostasis, he complained of abdominal pain and fever, and an abdominal radiograph