ABSTRACT
Cardiopulmonary events account for many of the serious gastrointestinal endoscopy complications. Pulse oximetry monitoring detects hypoxemia to allow prevention of complications. Alternatively, prophylaxis by continuous nasal oxygen during the procedure may offset any tendency toward oxygen desaturation. We monitored patients with major upper gastrointestinal hemorrhage by pulse oximetry during emergency upper endoscopy on room air or while receiving supplemental nasal oxygen (2 l/min). Desaturation (SpO2 < 90%) occurred in 80% of patients undergoing emergency procedures on room air but in only 25% of those receiving supplemental oxygen. For comparison, patients without significant cardiac or pulmonary disease undergoing elective procedures were studied on room air and desaturation only occurred in 29%. Thus, arterial oxygen desaturation as measured by pulse oximetry occurs more often during emergency than elective endoscopy. Supplemental oxygen decreases desaturation during emergency endoscopy but does not abolish it. We recommend that supplemental oxygen be used during emergency endoscopy to decrease desaturation, but it should not substitute for patient monitoring.