Endoscopic Management of Acute Lower Gastrointestinal Bleeding

Abstract

Lower gastrointestinal bleeding (LGIB) continues to be a problem for physicians. Acute LGIB is defined as bleeding that emanates from a source distal to the ligament of Treitz. Although 80% of all LGIB will stop spontaneously, the identification of the bleeding source remains challenging and rebleeding can occur in 25% of cases. Diverticular bleeding remains the most common cause of lower GI bleeding. Lower Gastrointestinal Bleeding encompasses a wide clinical spectrum ranging from occult bleeding to overt hematochezia until massive hemorrhage with shock requiring emerging hospitalization. Some patients with severe hematochezia require urgent attention to minimize further bleeding and complications. Colonoscopy is the diagnostic procedure of choice in most patients with Lower GI bleeding and its role in the treatment of lower GI bleeding has been shown to be an efficacious and safe method even if a therapeutic endoscopy occurred in about 30% of patients. The optimal timing of colonoscopy in LGIB remains to be determined. CT angiography is used in the setting of acute Lower GI bleeding correctly depicts the presence and location of active or recent hemorrhage, as well as the potential cause, in about 80-85% of case. Nuclear scintigraphy has been proposed as a diagnostic screening prior to angiography, increasing the likelihood of positive angiographic results or as a tool for localization for surgery but had multiple limitations. Superselective mesenteric angiography remains the cornerstone of management of patients with acute LGIB but it is an invasive and time-consuming procedure. Emergent surgery should be considered only as a last resort and is rarely needed to prevent death from exanguination. The golden standard for surgical treatment of acute severe LGIB should be directed segmental resection based on aggressive preoperative identification of the bleeding site. This article reviews the causes, clinical presentation, diagnostic methods, endoscopic treatment of LGIB and management of specific LGI bleeding lesions.