Lower Gastrointestinal Tract Bleeding

Abstract

Introduction: Lower gastrointestinal bleed (LGIB) is defined as blood loss originating in the alimentary tract distal to the ligament of Treitz. It can be classified as acute and chronic. The incidence rises with increasing age and the frequent use of antithrombotic agents in the elderly population. Etiology: Diverticulosis is the most common etiology, followed by angiodysplasia. Colitis can be grouped as ischemic, infectious, and inflammatory bowel disease. Post-polypectomy bleeding, anorectal causes. Small bowel causes, including Crohn’s ileitis, Meckel’s diverticula, tumors, vascular ectasia, and upper GI bleeding. Initial Assessment and Management: It is important to assess hemodynamic stability and resuscitate if necessary, complete history & physical, labs, and nasogastric tube placement with lavage and esophagogastroduodenoscopy (EGD) in some cases. The next step is to evaluate the severity of the bleed, identify the potential sources, and determine if other disorders are present that affect the management. Patients should be triaged according to their hemodynamic status, placed on NPO status, O2, and two large-bore IVs or central line, consider intubation if unstable. IV fluid resuscitation and blood transfusion, after type and cross, should be individualized but consider if hemoglobin is below 7 g/dl for most patients. Antithromobotic agents should be held, with transfusion of FFP and platelets as needed. A therapeutic endoscopist, interventional radiologists, and a general surgeon should be timely consulted. Diagnostic and Treatment Options: A colonoscopy should be the initial exam of choice; however, if upper GI bleeding is suspected, an EGD should be performed first. Radionuclide imaging, computed tomography angiography, and mesenteric angiography all need active bleeding at the time of exam. Surgery in patients with lower gastrointestinal bleeding should be reserved as a last resort when other options have failed; the alternatives go from segmental small bowel resection with intraoperative enteroscopy to subtotal colectomy.