Anesthesiologists have recognized the increased risk inherent in obstructive sleep apnea patients, yet studies on sleep apnea and endoscope procedures are limited. As more procedures are being done in clinics, ambulatory care centers, and procedures labs, nurses are now performing moderate sedation on this high risk patient population with little information to guide them. Of concern, 80-90% of the people who have obstructive sleep apnea are unaware they have it. This article will explore the definition of sleep apnea, identify risk factors, and review literature that relates to obstructive sleep apnea and moderate sedation procedures. A resource list of agencies, internet sites, and references are included. This review of obstructive sleep apnea can assist gastroenterology nurses administering sedation to better recognize and monitor this high risk group.