Effect of nitrous oxide on clinical outcome in patients undergoing cerebellopontine tumor surgery under sevoflurane anesthesia: a randomized controlled trial.

Nitrous oxide (NO) is a unique anesthetic agent that has both advantages and disadvantages, especially in neurosurgical patients. Various studies evaluating the use of NO in different surgical populations have been inconclusive so far. In this prospective, single-blinded, randomized study, 50 patients of either sex, aged 18-60 years, were enrolled and randomly allocated into NO or NO free group. Data including demographics, intraoperative vitals, blood gases, intravenous fluids, anesthetic drug consumption, brain condition, emergence and recovery time, duration of surgery and anesthesia, duration of postoperative ventilation, perioperative complications, condition at discharge, and duration of intensive care unit & hospital stay were recorded. There was no significant difference in intensive care unit or hospital stay between the groups. However, a significant difference in intraoperative heart rate and mean arterial pressure was observed. The incidence of intraoperative tachycardia and hypotension was significantly higher in the NO free group. Other intra- and post-operative parameters, perioperative complications, and conditions at discharge were comparable. Use of NO anesthesia for cerebellopontine tumor surgery in good physical grade and well-optimized patients neither increases the length of intensive care unit or hospital stay nor does it affect the complications and conditions at discharge. However, future studies in poor-grade patients with large tumors and raised intracranial pressure will be required to draw a definitive conclusion.