Background: Remimazolam and propofol can be used interchangeably for general anesthesia. However, no dosing recommendations exist for the intravenous bolus administration of remimazolam during general anesthesia induction in pediatric patients. Determining the appropriate dose for anesthesia induction in pediatric patients is crucial for safe and effective surgical procedures.
Objectives: The study aimed to determine the median effective dose (ED50) for loss of consciousness (LOC) with remimazolam and propofol in pediatric patients and establish the dose equivalence between these anesthetics.
Study design: A prospective, randomized, single-center trial.
Setting: A tertiary pediatric hospital in China from January 2023 to July 2023.
Methods: Pediatric patients aged 3 to 15 years, undergoing elective surgery under general anesthesia, were included. Patients were randomized to receive either remimazolam (in doses of 0.1, 0.15, 0.2, 0.25, and 0.3 mg/kg-1) or propofol (in doses of 0.75, 1.0, 1.25, and 1.5 mg/kg-1) via intravenous bolus. The primary measure consisted of determining the ED50 for LOC with remimazolam, and the secondary measure consisted of establishing the dose equivalence between remimazolam and propofol.
Results: The calculated ED50 for remimazolam was 0.19 mg/kg-1 (95% CI: 0.10-0.35), and that for propofol was 1.11 mg/kg-1 (95% CI: 0.53-2.15). This finding indicates that remimazolam is approximately 5.8 times more potent than propofol.
Limitations: In this study, the anesthesiologist could not be blinded to the different appearances of remimazolam and propofol, and the LOC assessment method may have introduced bias. Furthermore, the recommended dose for remimazolam induction was not tested directly within this trial, suggesting a need for further research.
Conclusions: Remimazolam demonstrates significantly higher sedative efficacy for pediatric patients than does propofol. An induction dose of 0.34 mg/kg-1 remimazolam could be recommended for general anesthesia induction, considering the safety and effectiveness of a 2 mg/kg-1 dose of propofol.
Keywords: dose equivalence; intravenous bolus administration; loss of consciousness (LOC); median effective dose (ED50); pediatric anesthesia; propofol; Remimazolam.