Evaluation of patients presenting with hematochezia (excluding those with minimal rectal bleeding)

IDA: iron deficiency anemia; CTA: computed tomographic angiography; CT: computed tomographic; GI: gastrointestinal; MR: magnetic resonance.
* If hematemesis or melena is present the patient should be evaluated for upper GI bleeding. Refer to UpToDate topics on the evaluation of upper GI bleeding for details.
¶ Bleeding associated with signs such as hypotension, tachycardia, or orthostatic hypotension.
Δ Colonoscopy should be performed once the patient has been resuscitated and an adequate bowel preparation has been given (typically 4 to 6 L of polyethylene glycol). If the initial colonoscopy was inadequate (eg, inadequate visualization, failure to reach the cecum), repeat colonoscopy should be considered.
◊ Consider evaluation with a side-viewing duodenoscope in patients with risk factors for hemobilia or hemosuccus pancreaticus or CT angiography (followed by push enteroscopy if the CT angiography is negative) in patients at risk for an aortoenteric fistula. Conventional transvenous angiography is typically performed if the patient remains hemodynamically unstable despite attempts at resuscitation. If the suspicion for an upper GI source is moderate (rather than high), nasogastric lavage can be performed to look for evidence to support an upper GI source. Refer to UpToDate topics on lower GI bleeding in adults for additional details.
§ CTA is an alternative but lacks therapeutic capacity. A tagged red blood cell scan may aid with localization prior to angiography.
¥ Refer to UpToDate topic review on suspected small bowel bleeding for details.
‡ Following successful angiography, an elective colonoscopy may still need to be performed to evaluate the underlying cause of bleeding (eg, large colorectal polyp or neoplasia).
† A Meckel's scan should be performed in younger patients with overt bleeding. Surgical exploration is appropriate if no other studies have revealed a source and significant bleeding continues or if there is high suspicion for a small bowel neoplasm.
** If the deep small bowel enteroscopy was incomplete, a video capsule endoscopy study should be obtained, followed by CT or MR enterography if the capsule endoscopy is negative.