Remimazolam-Flumazenil Versus Sevoflurane for Hysteroscopic Day Surgery

Ambulatory surgery has become an increasingly important component of modern healthcaresystems because it enables rapid recovery, early discharge, efficient utilization ofhospital resources, and improved patient satisfaction. The success of ambulatory surgerydepends largely on the ability to provide anesthetic care that ensures rapid emergence,minimal postoperative symptoms, and timely discharge without compromising patient safety.Hysteroscopic surgery is one of the most commonly performed ambulatory gynecologicprocedures and therefore represents an ideal model for evaluating anesthetic strategiesdesigned to optimize perioperative efficiency and recovery.Sevoflurane‐based balanced anesthesia, typically consisting of intravenous inductionfollowed by maintenance with a volatile anesthetic agent, remains one of the most widelyused anesthetic techniques for ambulatory surgery. Although this approach providesreliable hypnosis and favorable surgical conditions, recovery is dependent on anestheticelimination and individual patient characteristics. Furthermore, volatile anesthetics maycontribute to postoperative nausea and vomiting, which remain among the most commoncauses of delayed discharge and patient dissatisfaction following ambulatory procedures.Remimazolam is a novel ultra‐short‐acting benzodiazepine anesthetic that is rapidlymetabolized by nonspecific tissue esterases. Compared with conventional anestheticagents, remimazolam demonstrates predictable pharmacokinetics, limited accumulation,reduced respiratory depression, and favorable hemodynamic stability. Several clinicalstudies have shown that remimazolam may reduce the incidence and severity of hypotensioncompared with propofol while providing effective hypnosis for general anesthesia.However, concerns remain regarding delayed awakening and the possibility of residualsedation, particularly in short ambulatory procedures where rapid recovery is essential.A unique characteristic of remimazolam is the availability of flumazenil, a specificbenzodiazepine receptor antagonist capable of rapidly reversing its sedative effects.Planned administration of flumazenil at the end of surgery may allow faster and morepredictable emergence than spontaneous recovery alone. Despite this theoreticaladvantage, evidence supporting a structured remimazolam‐flumazenil anesthetic strategy inambulatory surgery remains limited. Most previous investigations have focused onpharmacodynamic comparisons between remimazolam and propofol, whereas direct comparisonswith inhalational balanced anesthesia have been relatively scarce. In addition, fewstudies have evaluated outcomes that are directly relevant to operating room efficiencyand perioperative workflow.The concept of anesthesia‐controlled time has been proposed as a clinically meaningfulmeasure of anesthetic efficiency because it incorporates both induction and emergencephases of anesthesia. Unlike isolated measurements of induction time or awakening time,anesthesia‐controlled time reflects the overall contribution of anesthetic management tooperating room utilization and turnover. Reductions in anesthesia‐controlled time mayimprove operating room throughput, increase institutional efficiency, and facilitatepatient flow in ambulatory surgery centers.This prospective, single‐center, randomized controlled trial is designed to compareremimazolam anesthesia with planned flumazenil reversal and sevoflurane‐based balancedanesthesia in adult women undergoing ambulatory hysteroscopic surgery. Eligibleparticipants will be randomly assigned in a 1:1 ratio to receive either remimazolam forinduction and maintenance followed by flumazenil reversal at the end of surgery orpropofol induction followed by sevoflurane‐based balanced anesthesia. Standardizedperioperative management protocols will be applied to both groups, including opioidadministration, neuromuscular blockade, supraglottic airway management, andelectroencephalographic monitoring using the Patient State Index (PSI).The primary outcome will be anesthesia‐controlled time, defined as the sum of inductiontime and emergence time. Induction time will be measured from initiation of theanesthetic agent to successful placement of the supraglottic airway device, whileemergence time will be measured from discontinuation of the primary anesthetic agent toremoval of the airway device. This endpoint was selected because it directly reflectsoperating room efficiency and represents a clinically relevant outcome in ambulatorysurgical practice.Secondary outcomes will evaluate multiple aspects of recovery quality and patient safety.These outcomes include time to achieve an Aldrete score of at least 9, duration of stayin the post‐anesthesia care unit, postoperative nausea and vomiting, sore throat,surgical pain, shivering, dizziness, vasopressor requirements, and quality of recoveryassessed using the validated Quality of Recovery‐15 (QoR‐15) questionnaire. The incidenceof re‐sedation will be evaluated using the Modified Observer's Assessment ofAlertness/Sedation (MOAA/S) scale together with electroencephalographic monitoring data.Additional recovery variables, including time to eye opening, time to PSI recovery, andtime to airway device removal, will also be assessed.The investigators hypothesize that remimazolam anesthesia with planned flumazenilreversal will reduce anesthesia‐controlled time and improve perioperative efficiencywhile maintaining recovery quality and safety comparable to conventionalsevoflurane‐based balanced anesthesia. The findings of this study may provide clinicallyrelevant evidence regarding the optimal anesthetic strategy for ambulatory hysteroscopicsurgery and may support broader implementation of remimazolam‐based anesthesia inshort‐duration surgical procedures.