1264 EEG-Guided Volatile Anesthesia in Complex Neurosurgical Procedures: A Case Series and Proposal for a Novel Protocol

INTRODUCTION: Total Intravenous Anesthesia (TIVA) has been widely adopted in neurosurgery. TIVA is favored for its ability to maintain a stable hemodynamic profile and control intracranial pressure. In addition, TIVA has been shown to have minimal impact on neurophysiological monitoring. Despite these advantages, EEG-guided volatile anesthesia in neurosurgery presents a compelling alternative. Utilizing EEG, specifically, density spectral array (DSA), anesthetic delivery can be tailored to individual physiological needs. EEG-guided volatile anesthesia is shown to contribute to a reduced length of hospital stay (LOS), associated with lower healthcare costs, reduced post-operative delirium, and improved patient satisfaction. METHODS: Six patients were included in this study. SedLine® was used in 4 and standard neuromonitoring EEG was used for the remaining. Primary outcome was the “time to regain full consciousness,” defined as the time required to correctly respond to time/space orientation and perform 2-step commands. Data was extracted and analyzed using R version 4.3.2. RESULTS: Four cranial and two spine deformity procedures were performed. Mean age was 63.5±9.4 years and mean duration of surgery was 184±26 minutes. Patients with EEG-guided volatile anesthesia exhibited notably rapid emergence. The mean time between the last stich and full consciousness was 206±253 seconds. Both brain activity monitoring using SedLine® and a standard EEG reader revealed similar patterns particularly on the Density Spectral Array (DSA). CONCLUSIONS: This study suggests that EEG-guided volatile anesthesia may facilitate decreased time to neurological assessment. This approach may be non-inferior to TIVA for neurosurgical procedures and may be implemented even in settings where the SedLine® is not available. Further prospective, case controlled, studies are necessary for further validation.