Does sleep apnea increase the risk of cardiorespiratory complications during endoscopy procedures?

Background: Patients with obstructive sleep apnea (OSA) have an increased risk of perioperative complications. Aim: The purpose of this study is to assess whether OSA increases the risk of cardiorespiratory complications in patients undergoing endoscopic procedures. Methods: A retrospective study was performed. We identified all patients who had undergone both an endoscopic procedure under conscious sedation and a sleep study from January 2001 to May 2008. Patients were divided into four groups: OSA negative (apnea-hypopnea index (AHI) < 5/h), OSA positive; mild: AHI 5-15/h, moderate: AHI 15.1-30/h, and severe: AHI > 30/h. Minor and major complications were identified. The minor ones were hypertension, hypotension, bradycardia, tachycardia, oxygen desaturation (<90%), and bradypnea. Major complications included chest pain, respiratory distress, cardiorespiratory arrest, or any minor complication that required intervention. Results: Procedures were performed in 639 patients: colonoscopies 68.5%, upper endoscopies 20.2%, and combined procedures 11.3%. The mean age was 60.5 years, mean body mass index 33.7, and 93% were males. Sleep study results: 130 negative, 509 positive; 135 mild, 125 moderate, and 249 severe. Of the patients, 19% had minor complications, while 7% had major complications. There was no significant difference between the patients with and without OSA in the rate of minor complications (odds ratio 1.17, 95% confidence interval 0.70-1.92) or major complications (odds ratio 1.19, 95% confidence interval 0.54-2.63). The odds ratio was also not significantly increased when a cutoff value of 10 or 15/h was used to delineate a positive sleep study. Conclusion: For patients undergoing endoscopy procedures under conscious sedation, the presence of OSA does not clearly increase the risk of cardiorespiratory complications.