2.4. General anesthesia protocol
All patients were randomly managed by staff anesthesiologists at each hospital. None of the patients received any premedication. Standard monitoring included electrocardiography, noninvasive blood pressure or arterial blood pressure monitoring, pulse oximetry, capnography, electroencephalogram-based monitoring using the bispectral index (BIS, Aspect Medical Systems, Newton, MA) at Hiroshima University Hospital or Spectral Entropy (GE Healthcare, Helsinki, Finland) at JA Hiroshima General Hospital, and neuromuscular monitoring via train-of-four monitoring.General anesthesia was induced with a continuous intravenous infusion of remifentanil at 0.25 µg/kg/min, followed by continuous infusion of remimazolam at 12 mg/kg/h in group R or target-controlled infusion of propofol with an initial target of 3 µg/mL in group P. Remifentanil doses were calculated based on actual body weight for patients with a BMI < 25 and ideal body weight for patients with BMI ≥ 25. Other anesthetics were calculated based on actual body weight. Rocuronium was administered at 0.6 mg/kg only for intubation. Following anesthesia induction, the ventilator settings were adjusted to maintain an oxygen saturation (SpOIn both groups, for anesthesia maintenance, remifentanil was maintained at approximately 0.25 µg/kg/min and tapered to 0.05 µg/kg/min after ropivacaine wound infusion before skin closure. Remimazolam or propofol was adjusted to keep the BIS or state entropy values in the range of 40 to 60 after the patients lost consciousness.The criteria for extubation are as follows: SpOWe measured the following times: from discontinuing administration of anesthetics to eye-opening, obeying commands, extubation, and achieving a white fast-track score (WFTS) of 12. The WFTS was used to evaluate the ability to be discharged from the OR (see Supplementary Table S1 online, 