Intermittent General Anesthesia With Controlled Ventilation for Asleep-Awake-Asleep Brain Surgery: A Prospective Series of 140 Gliomas in Eloquent Areas

BACKGROUND: Awake brain tumor surgery is a unique opportunity for mapping sensorimotor and cognitive functions, allowing the operator to optimize the resection while preserving the patient's quality of life. During this type of procedure, active participation of the patient is necessary. OBJECTIVE: To assess the efficacy and safety of a method of intermittent general anesthesia with controlled ventilation for performing invasive cerebral mapping. METHODS: We report our prospective and observational single-center study with an asleep-awake-asleep protocol. Aspects of feasibility, airway management, timing of each phase, and occurrence of adverse events were detailed. RESULTS: During a 35-month period, 140 patients underwent resection of a glioma in an eloquent area. During the asleep phases, controlled ventilation with a laryngeal mask was always efficient. Orotracheal intubation was performed for some patients for the second asleep period. The patients remained fully awake for a mean time of 98 minutes. Postural discomfort was reported in 17.8% of cases. There was 1 case of aspiration of gastric contents with a favorable outcome and no mortality. CONCLUSION: Intermittent general anesthesia with controlled ventilation for this type of neurosurgical procedure remains an anesthesiological challenge. However, the results of this study suggest that it may be feasible, reproducible, and relatively safe in the context of a standardized protocol involving members of both anesthesiology and surgery teams. Such a technique has a great potential to improve the surgical results, from both oncological and functional perspectives.