Comparison of recovery profiles between total intravenous anaesthesia with propofol or remimazolam reversed with flumazenil in patients undergoing breast surgery

BACKGROUND Remimazolam, a short acting benzodiazepine, is being used for general anaesthesia. The results of studies comparing recovery after propofol with that of remimazolam are inconsistent. Given that flumazenil reverses the sedative effects of remimazolam, we hypothesised that it would speed up recovery from remimazolam general anaesthesia. OBJECTIVES The aim of this trial was to compare the speed of recovery from general anaesthesia between propofol and remimazolam reversed with flumazenil in patients undergoing minimally invasive breast surgery. DESIGN Randomised, single-centre, double-blind controlled trial. SETTING A tertiary teaching hospital in South Korea from August 2022 to December 2022. PATIENTS Adult patients (≥19 years of age) about to undergo general anaesthesia for scheduled breast cancer surgery. INTERVENTIONS Patients were randomly allocated to either the propofol or the remimazolam/flumazenil group. The emergence process was monitored by only one anaesthesiologist. MAIN OUTCOME MEASURES The primary outcome was the time to eye opening to command during recovery from the general anaesthesia. Time to removal of the supraglottic airway (SGA) time to discharge, and the Riker sedation agitation scale (SAS) score (1 to 4) during emergence were compared as secondary outcomes. RESULTS The remimazolam group had a significantly shorter mean time to eye opening than the propofol group [127 ± 51 vs. 314 ± 140 s; mean difference 187 s (95% confidence interval (CI), 133 to 241 s; P < 0.001]. The remimazolam group also had shorter times to SGA removal [169 ± 51 vs. 366 ± 149 s; mean difference 198 s (95% CI, 140 to 255 s); P < 0.001] and time to discharge from the operating room [243 ± 55 vs. 449 ± 159 s; mean difference 206 s (95% CI, 145 to 267 s); P < 0.001]. The SAS scores during emergence also differed significantly, with 1 patient in the propofol group and 25 in the remimazolam group attaining scores of 4 ( P < 0.001). CONCLUSION Administration of remimazolam with flumazenil may be a promising option for patients undergoing breast cancer surgery, providing faster recovery and better SAS scores than propofol during emergence from general anaesthesia. TRIAL REGISTRATION ClinicalTrials.gov (NCT05435911).