Incidence of occult upper gastrointestinal bleeding in patients presenting to the ED with hematochezia

Objective: The aim of the study was to determine the incidence of nasogastric (NG) aspiration revealing a clinically unsuspected upper gastrointestinal (GI) bleeding in patients presenting to the emergency department (ED) with hematochezia. A secondary aim was to identify factors associated with an upper GI source. Methods: Data were prospectively collected from patients 18 years or older with either bright red blood per rectum or maroon stools. Patients were excluded if their history revealed hematemesis or their examination revealed melena, bleeding from an external hemorrhoid, or anal fissure. An NG tube was placed, and initial and postlavage aspirates were inspected and tested with Gastrocult (Beckman Coulter, Inc, Palo Alto, CA) for the presence of blood. Additional data included demographics, history, vital signs, and laboratory results. Results: Of 114 patients, 11 (9.6%; 95% confidence interval, 4.9%-16.6%) had a positive NG aspirate. There were no statistically significant differences in age, sex, or race between the 2 groups. Factors associated with a positive aspirate were history of upper GI bleeding (P = .04), heart rate (P = .055), and hemoglobin (P = .03). Conclusion: Patients presenting to the ED with hematochezia require NG tube placement and aspiration to exclude an upper GI source of bleeding. History of an upper GI bleeding and anemia were associated with a positive NG aspirate.