Assessment of the Berlin Questionnaire for evaluation of hypoxemia risk in subjects undergoing deep sedation for screening gastrointestinal endoscopy

BACKGROUND: Subjects with obstructive sleep apnea (OSA) are vulnerable to sedation-related complications during endoscopic procedures. A significant portion of subjects undergoing routine endoscopy is at high risk of OSA, but most are undiagnosed. The purpose of this study was to estimate the prevalence of high risk for OSA among Chinese subjects undergoing deep sedation for screening gastrointestinal endoscopy and to evaluate the hypoxemia risk of these examinees stratified by Berlin Questionnaire (BQ). PATIENTS AND METHODS: We performed a prospective cohort study in subjects undergoing deep sedation with monitored anesthesia care for combined esophagogastroduodenoscopy plus colonoscopy. Subjects who were Chinese were stratified into high- and low-risk groups for OSA by administration of BQ. Deep sedation was achieved via a propofol target-controlled infusion system. Hypoxemia was defined as pulse oximetry reading of less than 90%. The frequency of hypoxemia was compared between high- and low-risk groups for OSA. RESULTS: A total of 615 Chinese subjects were recruited during the study period, and 614 subjects were included for analysis. Two hundred eighteen (35.5%) subjected were classified to be at high risk of OSA, and 396 (64.5%) were stratified to be at low risk of OSA by BQ. Hypoxemia occurred in 83 (13.5%) subjects during endoscopy procedures. The risk of developing hypoxemia in the high-risk group was significantly higher when compared to that of the low-risk group subjects (24.8% vs 7.3%; relative risk, 3.37; 95% CI, 2.22–5.13). CONCLUSION: About one-third Chinese subjects undergoing deep sedation for screening endoscopy were at high risk of OSA. Subjects at high risk of OSA are associated with an increased risk of hypoxemia in comparison to the low-risk group when undergoing deep sedation for screening gastrointestinal endoscopy.