Reconsideration of Augmentation Strategies in Electroconvulsive Therapy: Effects of the Concurrent Use of a Reduced Dose of Propofol with Divided Supplemental Remifentanil and Moderate Hyperventilation on Electroconvulsive Therapy-Induced Seizure Production and Adverse Events

Background: Although several treatment strategies to enhance the efficacy of electroconvulsive therapy (ECT) have been discussed, there have been no reports on the combined use of these treatments. The purpose of this study was to evaluate the efficacy and safety of concurrent use of moderate hyperventilation and a reduced dose of propofol combined with divided remifentanil in ECT practice. Methods: Sixty patients scheduled to receive a total of 300 ECT treatments were randomly assigned to have the three interventions: a standard dose (1 mg/kg) of propofol (group P/N); a standard dose of propofol and moderate hyperventilation with end-tidal pressure of carbon dioxide (ETCO2) of 30 35 mmHg (group P/H); and a reduced dose (0.5 mg/kg) of propofol with divided supplemental remifentanil and moderate hyperventilation (group RP/H). Patients in group RP/H received remifentanil 1 μg/kg followed by propofol 0.5 mg/kg for unconsciousness and thereafter remifentanil 1 μg/kg immediately before the ECT stimulus. Results: Patients in Corresponding author. K. Nishikawa, M. Yamakage 220 group RP/H showed significantly longer durations of electroencephalographic (EEG) seizures in the early phase of ECT course (P < 0.01 and 0.05) and lower electrical stimulus in the late phase of ECT course (P < 0.05 in each) than those in groups P/N and P/H, respectively. Conclusions: The use of a reduced dose of propofol combined with divided supplemental remifentanil under moderate hyperventilation during ECT can offer advantages over the use of a standard dose of propofol with or without moderate hyperventilation in terms of more seizure augmentation and/or lower electrical stimulus.