Decrease in heart rate following the administration of sugammadex in adults

Background and Aims: Sugammadex is a novel agent for reversal of steroidal neuromuscular blocking agents (NMBAs) with potential advantages over acetylcholinesterase inhibitors. In preclinical trials, there have been rare instances of bradycardia with progression to cardiac arrest. To better define this issue, its incidence and mitigating factors, we prospectively evaluated the incidence of bradycardia after sugammadex administration in adults. Material and Methods: Patients ≥ 18 years of age who received sugammadex were included in this prospective, open label trial. After administration, heart rate (HR) was continuously monitored. HR was recorded every minute for 15 minutes and then every five minutes for the next 15 minutes or until patient was transferred out of the operating room. Bradycardia was defined as HR less than 60 beats/minute (bpm) or decrease in HR by ≥ 10 beats per minute (bpm) if the baseline HR was <70 bpm. Results: The study cohort included 200 patients. Bradycardia was observed in 13 cases (7%; 95% confidence interval: 4, 11), occurring a median of 4 minutes after sugammadex administration (IQR: 4, 9, range: 2-25). Among patients developing bradycardia, two (15%) had cardiac comorbid conditions. One patient received treatment for bradycardia with ephedrine. No clinically significant blood pressure changes were noted. On bivariate analysis, patients receiving a higher initial sugammadex dose were more likely to develop bradycardia. On multivariable logistic regression, initial sugammadex dose was not associated with the risk of bradycardia. Conclusion: The incidence of bradycardia after administration of sugammadex in our study was low and not associated with significant hemodynamic changes.