Sevoflurane in electroconvulsive therapy: A systematic review and meta-analysis of randomised trials

Sevoflurane is the most commonly used inhaled anaesthetic in electroconvulsive therapy (ECT). The objective of this study was to provide an up-to-date and comprehensive review on how the use of sevoflurane affects seizure adequacy (seizure duration and postictal suppression index [PSI]) and circulatory dynamics in ECT. We performed a meta-analysis of RCTs that investigated seizure adequacy and circulatory dynamics in patients treated with ECT using sevoflurane (sevoflurane group) and intravenous anaesthetics (non-sevoflurane group). A total of 12 RCTs (377 patients and 1339 ECT sessions) were included. Sevoflurane significantly decreased the electroencephalogram (EEG) seizure durations in comparison with intravenous anaesthetics, whereas no significant difference was observed in PSI (EEG: 9 studies, standardized mean difference (SMD) = 0.74, 95% confidence interval (CI) = -1.11 to -0.38, p = 0.0002; PSI: 4 studies, SMD = -0.06, CI -0.13 to 0.25, p = 0.59). The use of sevoflurane in ECT significantly increased heart rate (HR) compared with intravenous anaesthetics (9 studies, SMD = 0.31, CI 012-0.51, p = 0.004). In the pre-planned subgroup analysis, sevoflurane significantly reduced seizure duration compared with other types of anaesthetics, including propofol, barbiturates and ketamine. Furthermore, it was found that the risk of adverse events in ECT with sevoflurane were not significantly different from intravenous anaesthetics (6 studies, risk ratio = 1.33, CI 0.95-1.86, p = 0.09), with agitaion being the most common adverse effects. The results of our study suggest that using sevoflurane for ECT significantly reduces seizure duration, increases maximum HR and brings about no difference in the adverse event risk compared with those using intravenous anaesthetics for ECT. Therefore, there may not be compelling evidence favouring sevoflurane use for ECT, except in cases where intravenous access is difficult.