Acute gastrointestinal (GI) bleeding is one of the most common emergencies encountered during training. Whether called to evaluate hematemesis in the intensive care unit or hematochezia in the emergency department, the priority is stabilizing the patient - not setting up the endoscopy cart. A systematic approach centered on resuscitation, risk stratification, appropriate timing of endoscopy, and multidisciplinary communication leads to the best outcomes.
The initial assessment should always begin with the patient's hemodynamic status. Start with the familiar ABCs - airway, breathing, and circulation. Evaluate for hypotension, tachycardia, altered mental status, or other signs of shock. Patients with ongoing massive hematemesis or an inability to protect their airway may require endotracheal intubation before endoscopy. Establish two large-bore intravenous lines, obtain laboratory studies, including a complete blood count, comprehensive metabolic panel, coagulation studies, type and screen, and begin fluid resuscitation as indicated. A restrictive transfusion strategy is recommended for most patients, with transfusion generally initiated when the hemoglobin falls below 7 g/dL unless cardiovascular disease, active myocardial ischemia, or ongoing hemorrhagic shock warrants earlier intervention.
Clinical presentation often helps distinguish upper from lower GI bleeding. A useful bedside approach is to first identify the bleeding orifice (mouth versus rectum) and then assess the color of the blood, which ranges from bright red to black and tarry. Hematemesis and melena strongly suggest an upper GI source, whereas hematochezia typically indicates lower GI bleeding. However, brisk upper GI hemorrhage can also present with bright red blood per rectum, particularly in hemodynamically unstable patients. An elevated blood urea nitrogen (BUN)-to-creatinine ratio may support an upper GI source, with ratios greater than 20 increasing the likelihood of upper GI bleeding, although this finding should always be interpreted within the overall clinical context. Risk stratification tools, including the Glasgow-Blatchford Score, AIMS65, and Rockall score, may assist in predicting clinical outcomes and guiding disposition, but they should complement clinical judgment.
For suspected non-variceal upper GI bleeding, intravenous proton pump inhibitor therapy should be started promptly while arranging upper endoscopy, ideally within 24 hours after stabilization. Common etiologies include peptic ulcer disease, Mallory-Weiss tears, Dieulafoy lesions, angioectasias, and upper GI malignancies. Endoscopic hemostasis can be achieved using several different therapeutic modalities tailored to the bleeding lesion. Patients with suspected variceal hemorrhage require additional therapy. Intravenous octreotide and prophylactic antibiotics should be initiated immediately, even before endoscopy. Upper endoscopy should be performed urgently, ideally within 12 hours, with endoscopic band ligation serving as the preferred treatment for esophageal varices.
Lower GI bleeding is commonly caused by diverticular disease, angioectasias, ischemic colitis, post-polypectomy bleeding, colorectal neoplasia, or anorectal disorders. Following stabilization, patients should undergo bowel preparation before colonoscopy when feasible. Rapid bowel preparation should be undertaken cautiously, as administration of large-volume polyethylene glycol solutions may increase the risk of aspiration in selected patients. Colonoscopy should be performed after adequate hemodynamic stabilization and bowel preparation. Although urgent colonoscopy may be appropriate for selected high-risk patients with ongoing bleeding, current evidence has not consistently demonstrated improved clinical outcomes compared with elective inpatient colonoscopy. If bleeding remains brisk, the patient is hemodynamically unstable, or visualization during colonoscopy is inadequate, computed tomography angiography can rapidly localize active hemorrhage and guide transcatheter arterial embolization. Early consultation with interventional radiology and colorectal surgery should be considered for patients with ongoing hemodynamic instability or failure of endoscopic therapy.
Endoscopic hemostatic therapies can be broadly categorized as injection, thermal, mechanical, topical, and combination therapies. Injection with dilute epinephrine provides temporary tamponade and local vasoconstriction but should not be used as definitive monotherapy because it does not provide durable hemostasis. Thermal therapies include heater probe, bipolar electrocoagulation, argon plasma coagulation, and coagulation forceps. Mechanical therapies include through-the-scope (TTS) clips, over-the-scope clips (OTSC), and endoscopic band ligation, which remains the treatment of choice for esophageal variceal bleeding. Topical hemostatic therapies, including hemostatic powders and peptide-based matrices, create a mechanical barrier over the bleeding site and are particularly useful when conventional techniques are technically difficult or as rescue therapy. Combination therapy using complementary modalities - most commonly injection followed by mechanical or thermal therapy - provides more durable hemostasis and reduces the risk of rebleeding compared with injection therapy alone.
One of the most important responsibilities of the trainee is recognizing when immediate endoscopy is appropriate and when delaying intervention to optimize the patient's condition is the safer approach. Patients who remain hypotensive despite aggressive resuscitation, have uncontrolled coagulopathy, or require airway stabilization should not be rushed to the endoscopy suite before these issues are addressed and a multidisciplinary discussion has identified strategies to minimize procedural risk. Informed consent should be obtained from the patient or an appropriate surrogate decision-maker whenever possible. If the patient lacks decision-making capacity and no surrogate is immediately available, emergency consent should be obtained according to institutional policy. Additionally, reviewing prior endoscopy reports, confirming antithrombotic medications, and communicating the clinical plan with the referring team, anesthesia, nursing staff, and the attending endoscopist are essential components of high-quality patient care.
Acute GI bleeding can be a daunting emergency for trainees, but success depends on organized clinical decision-making rather than technical endoscopic expertise alone. By following a structured approach - stabilizing the patient, localizing the bleeding source, initiating appropriate medical therapy, performing timely endoscopy, and involving multidisciplinary teams early - these common but high-risk presentations can be managed safely and effectively.
Key Concepts for GI Bleeding Emergencies
- Stabilization always takes priority over endoscopy.
- Use the bleeding orifice and the color continuum of the blood to help localize the source but always consider an upper GI source in unstable patients with hematochezia.
- Transfuse most patients using a restrictive hemoglobin threshold of 7 g/dL unless clinical circumstances, such as cardiovascular disease or ongoing hemorrhagic shock, warrant a higher threshold.
- Initiate intravenous proton pump inhibitors for suspected non-variceal bleeding and octreotide plus prophylactic antibiotics for suspected variceal bleeding.
- Perform upper endoscopy within 24 hours for most upper GI bleeds and within 12 hours for suspected variceal hemorrhage.
- Perform colonoscopy after adequate hemodynamic stabilization and bowel preparation. Urgent colonoscopy should be reserved for selected patients with ongoing or severe lower GI bleeding.
- Select endoscopic hemostatic therapy based on the bleeding lesion, using combination therapy whenever appropriate to improve durable hemostasis and reduce rebleeding.
- Engage anesthesia, interventional radiology, surgery, critical care, and other multidisciplinary teams early when managing massive, refractory, or persistently unstable GI hemorrhage.
Citations
- Khakoo NS, Laine L, Barkun AN, et al. ACG Clinical Guideline: Upper Gastrointestinal and Ulcer Bleeding. Am J Gastroenterol. 2021;116:899–917.
- Khakoo NS, Strate LL, Gralnek IM, et al. ACG Clinical Guideline: Management of Patients With Acute Lower Gastrointestinal Bleeding. Am J Gastroenterol. 2023;118:208–231.
- Gralnek IM, Stanley AJ, Morris AJ, et al. Endoscopic diagnosis and management of nonvariceal upper gastrointestinal hemorrhage: European Society of Gastrointestinal Endoscopy (ESGE) Guideline. Endoscopy. 2021;53:300–332.
- de Franchis R, Bosch J, Garcia-Tsao G, et al. Baveno VII—Renewing consensus in portal hypertension. J Hepatol. 2022;76:959–974.
- Richards RJ, Donica H, Grayer D, et al. Can the blood urea nitrogen/creatinine ratio distinguish upper from lower gastrointestinal bleeding? A diagnostic meta-analysis. Am J Emerg Med. 2019;37(11):1968–1973.
Author
Jake Barrett Wilson, MD is an Assistant Professor of Medicine in the Division of Gastroenterology and Hepatology at the Medical University of South Carolina. He is board certified in both Internal Medicine and Gastroenterology by the American Board of Internal Medicine. His academic interests include pancreaticobiliary diseases, interventional endoscopy, and the prevention of post-ERCP pancreatitis.