The effect of preoperative remimazolam application on emergence delirium in children under sevoflurane anesthesia based on electroencephalogram analysis: a randomized, double-blind, placebo-controlled study

OBJECTIVE: To explore the effect of preoperative application of remimazolam on electroencephalogram (EEG) epileptiform discharges in children under sevoflurane anesthesia, and whether it can affect the incidence of emergence delirium (ED) by influencing epileptiform discharges. METHODS: Sixty-two children aged 1 to 6 years who were scheduled to undergo tonsillectomy or adenoidectomy under sevoflurane anesthesia were selected as the research subjects and randomly divided into the remimazolam group (Group R) and the control group (Group C), with 31 cases in each group. Group R received remimazolam (0.2 mg/kg IV bolus) 2 min before induction; Group C received equivalent normal saline. The primary outcome was the incidence of ED. The secondary outcomes were the incidence of EEG epileptiform activity during induction, the time from sevoflurane induction to the appearance of the first epileptiform discharge, the peak score of the Paediatric Anaesthesia Emergence Delirium (PAED), extubation time, changes in hemodynamic during induction, postoperative pain conditions and postoperative adverse events. RESULTS: There was no significant difference in the incidence of ED between the two groups (P = 0.605), and there was no significant difference in the peak PAED score (P = 0.210). The application of remimazolam reduced the incidence of EEG epileptiform discharges in group R (P = 0.041) and prolonged the time of first epileptiform activity (P < 0.001). Patients in group R demonstrated better hemodynamic stability and well postoperative pain management. There was no significant difference between the two groups in terms of extubation time and postoperative adverse events during anesthesia emergence. CONCLUSION: The use of remimazolam before sevoflurane anesthesia reduced epileptiform EEG activity and improved hemodynamics during induction. However, it did not reduce the incidence of ED. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2500104743(date:14/7/2025).