Factors Influencing Safety of Sedation in a Large Cohort of Patients Undergoing Advanced Endoscopic Procedures

Abstract

Purpose: Effective and safe sedation is an important determinant of success in advanced endoscopic procedures. This study was undertaken to determine sedation-related adverse events (SRAEs) and predictors of SRAEs. Methods: A prospectively maintained database for all patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) and upper endoscopic ultrasound (EUS) between January 2008 and June 2011 at a tertiary referral university-affiliated teaching hospital was reviewed. The study included 1,759 procedures (942 ERCP, 817 EUS, M/F 38.8/61.2%, age 55.9 ± 20 years, BMI 28.4 ± 7.4 kg/m2). The predominant mode of anesthesia was certified registered nurse anesthetist-assisted monitored anesthesia care (MAC) in 898 procedures, general anesthesia (GA) in 819 and registered nurse-assisted conscious sedation (CS) in 42 patient procedures. Multivariate logistic regression analysis was performed to identify predictors for SRAEs. Results: Out of 183 (10.4%) SRAEs, 172 were intra-procedural SRAEs (hypotension needing pressors (145 events), hypoxia (5 events), arrhythmias (12 events), unplanned intubations [8 events]), and 11 were recovery room SRAEs. Two procedures each under GA and CS were aborted because of agitation and inadequate sedation, respectively. All SRAEs were transient, and patients recovered completely. No deaths occurred. A significantly lower rate of SRAEs was noted in patients who had MAC (6.1%) versus GA (14.7%), p<0.001. Patients with ASA III and IV had higher intra-procedural SRAEs, at 16.5 and 20.4%, respectively. SRAEs in ERCP (11%) and EUS (8%) were comparable. Multivariate logistic regression identified age, sex, BMI, procedure duration, coronary artery disease (CAD) (odds ratio [OR] 1.73, p=0.017), renal disease (OR 3.12, p=0.002), malignancy (OR 1.59, p=0.035), ASA class (OR 1.61, p=0.003), and GA (OR 2.84, p<0.001) as the independent predictors for SRAEs. Conclusion: A combination of patient demographics (female sex, older age, high BMI), comorbidities (CAD, CKD, malignancy), GA as mode of anesthesia and higher ASA class are associated with increased SRAEs during advanced endoscopic procedures.Table: Table. Multivariate logistic regression analysis of factors associated with sedation related adverse events (SRAEs)