Remimazolam With Planned Flumazenil Reversal Versus Sevoflurane-based Balanced Anesthesia for Hysteroscopic Day Surgery: A Randomized Controlled Trial

Ambulatory surgery has become an increasingly important component of modern healthcare systems because it enables rapid recovery, early discharge, efficient utilization of hospital resources, and improved patient satisfaction. The success of ambulatory surgery depends 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 gynecologic procedures and therefore represents an ideal model for evaluating anesthetic strategies designed to optimize perioperative efficiency and recovery.

Sevoflurane-based balanced anesthesia, typically consisting of intravenous induction followed by maintenance with a volatile anesthetic agent, remains one of the most widely used anesthetic techniques for ambulatory surgery. Although this approach provides reliable hypnosis and favorable surgical conditions, recovery is dependent on anesthetic elimination and individual patient characteristics. Furthermore, volatile anesthetics may contribute to postoperative nausea and vomiting, which remain among the most common causes of delayed discharge and patient dissatisfaction following ambulatory procedures.

Remimazolam is a novel ultra-short-acting benzodiazepine anesthetic that is rapidly metabolized by nonspecific tissue esterases. Compared with conventional anesthetic agents, remimazolam demonstrates predictable pharmacokinetics, limited accumulation, reduced respiratory depression, and favorable hemodynamic stability. Several clinical studies have shown that remimazolam may reduce the incidence and severity of hypotension compared with propofol while providing effective hypnosis for general anesthesia. However, concerns remain regarding delayed awakening and the possibility of residual sedation, particularly in short ambulatory procedures where rapid recovery is essential.

A unique characteristic of remimazolam is the availability of flumazenil, a specific benzodiazepine receptor antagonist capable of rapidly reversing its sedative effects. Planned administration of flumazenil at the end of surgery may allow faster and more predictable emergence than spontaneous recovery alone. Despite this theoretical advantage, evidence supporting a structured remimazolam-flumazenil anesthetic strategy in ambulatory surgery remains limited. Most previous investigations have focused on pharmacodynamic comparisons between remimazolam and propofol, whereas direct comparisons with inhalational balanced anesthesia have been relatively scarce. In addition, few studies have evaluated outcomes that are directly relevant to operating room efficiency and perioperative workflow.

The concept of anesthesia-controlled time has been proposed as a clinically meaningful measure of anesthetic efficiency because it incorporates both induction and emergence phases of anesthesia. Unlike isolated measurements of induction time or awakening time, anesthesia-controlled time reflects the overall contribution of anesthetic management to operating room utilization and turnover. Reductions in anesthesia-controlled time may improve operating room throughput, increase institutional efficiency, and facilitate patient flow in ambulatory surgery centers.