Seizure adequacy and safety of remimazolam in electroconvulsive therapy for patients with psychiatric disorders: a double-blind randomized crossover trial

Abstract Introduction Electroconvulsive therapy (ECT) is an established and effective treatment for patients with medication-resistant psychiatric disorders. However, the optimal choice of anesthetic agent for ECT induction remains a subject of ongoing debate. Remimazolam, a novel ultra-short-acting benzodiazepine, has yet to be systematically evaluated in the context of ECT anesthesia. Method We conducted a prospective, double-blind, randomized, crossover trial in hospitalized patients scheduled for ECT. Participants were randomly assigned to different treatment sequences, receiving either remimazolam (0.2 mg/kg) or propofol (2 mg/kg) for anesthesia induction in a crossover manner. The primary outcome was EEG seizure duration. Secondary outcomes included seizure adequacy endpoint, anesthesia-related parameters and safety profiles. All analyses were performed using generalized linear mixed-effects models, with treatment condition, stimulus dose, and treatment sequence as fixed effects and participant-specific random intercepts. Results A total of 284 ECT sessions from 56 patients were included in the analysis. The remimazolam group demonstrated significantly longer EEG seizure duration (37.0 s vs. 18.5 s; p < 0.001) and EMG seizure duration (15.0 s vs. 9.0 s, p < 0.001), higher average seizure energy index (24,767.4 µV 2 vs. 15,702.7 µV 2 ; p < 0.001), and greater maximum sustained power (38,197.7 µV 2 vs. 30,833.7 µV 2 ; p < 0.001). However, remimazolam was associated with a higher incidence of post-ictal hypertension and tachycardia, as well as prolonged induction and recovery time. Conclusion Remimazolam is an effective anesthetic induction agent for ECT, offering superior seizure quality metrics compared to propofol. However, clinicians should remain vigilant regarding the potential for post-ictal cardiovascular hyperdynamic states. Trial registration Chinese Clinical Trial Registry (number: ChiCTR2500114332; date: December 10, 2025).