Ultrasound-guided lesser occipital nerve combined with great auricular nerve block for vestibular schwannoma craniotomy via a suboccipital retrosigmoid approach: a prospective, double-blind randomized controlled trial

Abstract

Abstract Purpose This aim of this study was to investigate the analgesic efficacy and safety of lesser occipital nerve combined with great auricular nerve block (LOGAB) for craniotomy via a suboccipital retrosigmoid approach. Methods Patients underwent vestibular schwannoma resection via a suboccipital retrosigmoid approach were randomly assigned to receive ultrasound-guided unilateral LOGAB with 5 ml of 0.5% ropivacaine (LOGAB group) or normal saline (NSB group). Numeric rating scale (NRS) scores at rest and motion were recorded within 48 h after surgery. Mean arterial pressure (MAP), heart rate (HR), opioid consumption and other variables were measured secondly. Results Among 59 patients who were randomized, 30 patients received ropivacaine, and 29 patients received saline. NRS scores at rest (1.8 ± 0.5 vs. 3.2 ± 0.8, P = 0.002) and at motion (2.2 ± 0.7 vs. 3.2 ± 0.6, P = 0.013) of LOGAB group were lower than those of NSB group within 48 h after surgery. NRS scores of motion were comparable except for 6th and 12th hour (P < 0.05) in the LOGAB group. In LOGAB group, MAP decreased significantly during incision of skin and dura (P < 0.05) and intraoperative opoid consumption was remarkably reduced (P < 0.01). Postoperative remedial analgesia was earlier in the NSB group (P < 0.001). No patients reported any adverse events. Conclusion Among patients undergoing craniotomy for vestibular schwannoma via a suboccipital retrosigmoid approach, LOGAB may be a promising treatment for perioperative analgesia and has the potential to maintain intraoperative hemodynamic stability. Clinical trial registration number Chictr.org.cn ChiCTR2000038798.