CLINICAL CONTROVERSIES Nasogastric Aspiration in Gastrointestinal Hemorrhage Opposing authors provide succinct, authoritative discussions of controversial issues in emergency medi- cine. Authors are provided the opportunity to review and comment on opposing presentations. Each topic is accompanied by an Editor’s Note that summarizes important concepts. Participation as an authoritative discussant is by invitation only, but suggestions for topics and potential authors can be submitted to the section editors. Editor’s note: Nasogastric aspiration has traditionally been a part of the initial treatment of patients with gastrointestinal hemorrhage. Recently, authors noting the unpleasantness of the procedure have begun questioning its benefits and have suggested alternative measures. In this installment of Clinical Controversies, “pro” and “con” advocates discuss opposing perspectives and present the available evidence and arguments that must be considered in deciding to initiate or withhold nasogastric aspiration in patients with gastrointestinal hemorrhage. NASOGASTRIC ASPIRATION: A USEFUL TOOL IN SOME PATIENTS WITH GASTROINTESTINAL BLEEDING Robert S. Anderson, MD Michael D. Witting, MD, MS University of Maryland School of Medicine, Department of Emergency Medicine, Baltimore, MD Traditionally, nasogastric aspiration has been considered a routine part of the emergency department (ED) evaluation of gastrointestinal hemorrhage. However, recent studies have emphasized the pain of this procedure and its limitations as a diagnostic test. 1,2 Some may take the extreme view that nasogastric aspiration is never useful. But in selected patients, aspiration of gastric contents is critical to rapid diagnosis and treatment. Nasogastric aspiration is safe, and topical anesthesia can decrease pain by two thirds. 3,4 In this article, we explore the strengths and weaknesses of this misunderstood test, with an emphasis on its utility in certain presentations. LOCALIZATION IN PATIENTS PRESENTING WITHOUT HEMATEMESIS Hematemesis indicates an upper gastrointestinal source; hematochezia or melena may result from anywhere in the gastrointestinal tract. Upper gastrointestinal hemorrhage can be controlled at the bedside with esophagoduodenoscopy, but lower gastrointestinal bleeding may require colonoscopy, angiography, or surgery. 5 Thus, in patients without hematemesis, nasogastric aspiration may identify patients with an upper gastrointestinal source that may be amenable to bedside treatment. The duodenum, an area inaccessible to nasogastric aspiration, is the most common upper gastrointestinal source in patients with rectal bleeding. 6 This, and the fact that nasogastric aspiration can detect only active bleeding, limits nasogastric aspiration’s ability to localize hemorrhage. Indeed, in detecting upper gastrointestinal bleeding in patients without hematemesis, nasogastric aspiration has poor sensitivity (42%), accuracy (66%), and likelihood ratio for a negative test result (0.6). However, a positive test result, found in 23% of cases, has a likelihood ratio of 11. 2 One could liken nasogastric aspiration to the nitrate test for a urinary tract infection: a positive test result is useful, but common disease processes may cause false-negative results. Unlike the nitrate test, nasogastric aspiration is painful and labor intensive, so its use requires judgment. Other clues, available noninvasively, also may indicate an upper gastrointestinal source: black stool (odds ratio 17), blood urea nitrogen/creatinine ratio greater than 30 (odds ratio 10), and age younger than 50 years (odds ratio 8). 7 Patients with brisk persistent hematochezia are a significant challenge for the emergency physician. Control of lower gastrointestinal bleeding may involve multiple consultants and transfer of unstable patients out of the ED. When control of brisk persistent rectal bleeding is needed, nasogastric aspiration may indicate cases that can be managed by esophagoduodenoscopy. ASSESSING BLOOD LOSS IN PATIENTS WITH HEMATEMESIS In patients with hematemesis, the question is not, Where is it coming from, but How fast is it bleeding right now? Nasogastric aspiration is the emergency physician’s only means to directly measure the rate of hemorrhage proximal to the pyloric sphincter. A recent study by Aljebreen et al 8 provided evidence in support of this traditional procedure. Among 520 patients, they found that those with a bloody aspirate were 3 times more likely to have lesions requiring endoscopic treatment than those with a clear or bilious aspirate (P.0001). In many patients, direct measurement of the rate of hemorrhage is not necessary. For example, nasogastric aspiration is unnecessary in patients presenting with coffee ground emesis because the time required for chemical change in the stomach indicates a slow rate of bleeding. Indirect methods of assessing 364 Annals of Emergency Medicine Volume , .  : April 