gastrointestinal bleeding, any bleeding from the GI tract. The most common underlying conditions are peptic ulcer, Mallory-Weiss syndrome, esophageal varices, diverticulosis, ulcerative colitis, and carcinoma of the stomach and colon. Vomiting of bright red blood or passage of coffee-ground vomitus indicates upper GI bleeding, usually from the esophagus, stomach, or upper duodenum. Aspiration of the gastric contents, lavage, and endoscopy are performed to determine the site and rate of bleeding. Tarry black stools indicate a bleeding source in the upper GI tract; bright red blood from the rectum usually indicates bleeding in the distal colon. GI bleeding is treated as a potential emergency. Patients may require transfusions, fluid replacement, endoscopic treatment, or gastric lavage and are watched carefully so as to prevent shock and hypovolemia. In all patients blood loss is evaluated and ability to coagulate is tested. See also coffee-ground vomitus, hematochezia, melena.
