Stereotactic Functional Neurosurgery Combining Sedation and Awake Procedures Using Remimazolam Besylate and Flumazenil: A Technical Note.

Abstract

Current anesthesia methods for stereotactic functional neurosurgery face significant limitations. Local anesthesia and mild sedation often lead to patient discomfort, while general anesthesia precludes real-time neurological assessments critical for optimizing therapeutic outcomes. This technical note introduces a novel sedation protocol using remimazolam besylate combined with flumazenil in 30 patients with movement disorders undergoing stereotactic functional neurosurgery between November 2022 and March 2024. Remimazolam besylate was administered intravenously for sedation while maintaining spontaneous respiration, with doses adjusted based on patient response and bispectral index values. Sedation was reversed using flumazenil, allowing patients to awaken for neurological assessments; the procedures then continued with patients awake. Fentanyl was used for analgesia, and no muscle relaxants were employed. All patients successfully tolerated the procedures, reporting no intraprocedural discomfort or pain. The mean time to awakening after flumazenil injection was 130.3 ± 73.9 secs. No significant adverse events, including respiratory depression or re-sedation, were observed. One patient experienced a panic attack due to severe claustrophobia, necessitating re-sedation with propofol. The absence of muscle relaxants facilitated effective intraoperative neurological assessments. Postoperative outcomes were positive for all patients. This sedation protocol demonstrated feasibility and safety, offering a promising solution to challenges associated with intraoperative sedation and neurological assessment in stereotactic functional neurosurgery. Further research involving larger cohorts is warranted to confirm these findings and explore broader applications of this technique.