Diverticular bleeding.

Diverticular bleeding is a common cause of lower gastrointestinal hemorrhage. Patients typically present with massive and painless rectal hemorrhage. If bleeding is severe, initial resuscitative measures should include airway maintenance and oxygen supplementation, followed by measurement of hemoglobin and hematocrit levels, and blood typing and crossmatching. Patients may need intravenous fluid resuscitation with normal saline or lactated Ringer's solution, followed by transfusion of packed red blood cells in the event of ongoing bleeding. Diverticular hemorrhage resolves spontaneously in approximately 80 percent of patients. If there is severe bleeding or significant comorbidities, patients should be admitted to the intensive care unit. The recommended initial diagnostic test is colonoscopy, performed within 12 to 48 hours of presentation and after a rapid bowel preparation with polyethylene glycol solutions. If the bleeding source is identified by colonoscopy, endoscopic therapeutic maneuvers can be performed. These may include injection with epinephrine or electrocautery therapy. If the bleeding source is not identified, radionuclide imaging (i.e., technetium-99m-tagged red blood cell scan) should be performed, usually followed by arteriography. For ongoing diverticular hemorrhage, other therapeutic modalities such as selective embolization, intra-arterial vasopressin infusion, or surgery, should be considered.