Urgent Colonoscopy for Lower Gastrointestinal Bleeding?

Is urgent colonoscopy necessary for patients with acute lower gastrointestinal (GI) bleeding? To address this question, researchers in California enrolled 85 patients (mean age, 52; mean hemoglobin concentration, 7.9 g/dL) with hemodynamically significant hematochezia, but no hemetemesis. Upper endoscopy, performed in all patients within 6 hours, revealed bleeding sources in 13 patients. The remaining 72 patients were randomized to urgent colonoscopy (performed within 12 hours of presentation) or elective colonoscopy (performed at 36–60 hours).

Sources of lower GI bleeding identified most often were diverticulae (25%) and internal hemorrhoids (20%); no source was found in 28% of patients. Further bleeding during the hospitalization, defined …