Randomized controlled trial comparing the effects of methoxyflurane and local anesthesia combination to local anesthesia alone in scrotal surgery.

Abstract

Introduction: Outpatient scrotal surgery under local anesthesia (LA) has been associated with excellent safety, tolerability, and efficacy; however, needle phobia and periprocedural anxiety remain areas for improvement. This study evaluated the efficacy of methoxyflurane as an adjunct to LA in alleviating pain and anxiety during local anesthesia-based scrotal urologic surgeries.

Methods: A non-blinded, randomized controlled trial was conducted at Men's Health Clinic Manitoba for patients undergoing scrotal surgery under LA. A power calculation determined a required sample size of 40. Patients were randomized to receive either LA alone or LA with inhaled methoxyflurane. Pain and anxiety were assessed pre- and postoperatively using a visual analog scale (VAS) and the State-Trait Anxiety Index (STAI). Comparisons of VAS pain scores and anxiety measures between groups were performed using the Mann-Whitney U-test.

Results: Forty patients underwent scrotal procedures under LA without intraoperative or postoperative adverse events. Patients in the methoxyflurane group reported similar intraoperative pain levels compared to the LA group (1.35 vs. 1.85, p=0.3); however, intraoperative anxiety in the methoxyflurane group was significantly less than the control group (0.4 vs. 1.65, p=0.01). Patients receiving methoxyflurane also reported significantly higher procedural tolerability compared to controls (9.6 vs. 7.4, p=0.01).

Conclusions: Scrotal surgery under LA is well tolerated; however, inhaled methoxyflurane as an adjunct to LA is an effective means of reducing anxiety and further improving patient-reported experiences during scrotal urologic procedures.