Gastrointestinal (GI) bleeding is a serious emergency that involves active blood loss from any part of the digestive tract, ranging from the esophagus to the rectum. It may present dramatically with visible blood or more subtly with weakness, dizziness, and anemia. Because significant bleeding can rapidly lead to shock and organ failure, immediate emergency evaluation and stabilization are essential.

GI bleeding is broadly classified into upper and lower sources. Upper GI bleeding originates from the esophagus, stomach, or duodenum and commonly presents with hematemesis (vomiting blood) or melena (black tarry stools). Common causes include peptic ulcer disease, gastritis, esophageal varices, Mallory-Weiss tears, or medication-related injury. Lower GI bleeding originates from the small intestine or colon and may present as bright red blood per rectum or maroon-colored stools. Causes include diverticulosis, inflammatory bowel disease, colitis, hemorrhoids, angiodysplasia, or colorectal malignancy.

Emergency evaluation begins immediately with airway, breathing, and circulation assessment. Patients with massive hematemesis are at risk of airway compromise and may require urgent airway protection. Continuous monitoring of blood pressure, heart rate, oxygen saturation, and mental status is initiated. Hypotension, tachycardia, pallor, and altered consciousness may indicate significant blood loss.

Intravenous access is established promptly, typically with large-bore lines, to allow rapid fluid resuscitation and blood transfusion if required. Laboratory tests include complete blood count, coagulation profile, kidney and liver function tests, and blood typing. Serial hemoglobin measurements help assess ongoing blood loss. In patients on anticoagulant therapy, reversal strategies may be necessary.

Risk stratification is critical. Indicators of severe bleeding include persistent hypotension, high heart rate, ongoing hematemesis, severe anemia, or signs of shock. High-risk patients require aggressive stabilization and urgent specialist consultation. Early involvement of gastroenterology ensures timely endoscopic evaluation once the patient is stable.

Imaging studies or endoscopy are used to identify the bleeding source. Upper endoscopy allows visualization and possible therapeutic intervention such as clipping, cauterization, or injection therapy. In lower GI bleeding, colonoscopy or imaging may be utilized depending on stability and bleeding severity.

Management focuses on resuscitation, identification of bleeding source, and definitive control. Proton pump inhibitor therapy may be administered in suspected ulcer bleeding. Variceal bleeding requires specialized protocols including vasoactive medications and coordinated endoscopic therapy. In cases where endoscopic control is unsuccessful, interventional radiology or surgical consultation may be required.

Continuous monitoring in the emergency setting is essential because re-bleeding may occur. Urine output, mental status, and vital signs provide important indicators of perfusion. Patients with significant blood loss may require admission to intensive care.

Rapid emergency management of GI bleeding prevents progression to shock, organ failure, and death. Structured protocols emphasizing immediate stabilization, risk assessment, and multidisciplinary coordination significantly improve outcomes and reduce mortality rates.