246. EFFECT OF INTRAOPERATIVE NERVE MONITORING DURING MINIMALLY INVASIVE ESOPHAGECTOMY

Abstract Background Recurrent laryngeal nerve (RLN) lymphadenectomy is a crucial step during esophagectomy. However, it is technically demanding and associated with a significant risk of RLN injury. Despite several studies demonstrating the feasibility of intraoperative nerve monitoring (IONM) during esophageal surgery, routine utilization of IONM during minimally invasive esophagectomy has not become common, and there is limited evidence to provide robust guidance. Here, we describe our experience with IONM during minimally invasive McKeown esophagectomy. Methods Data from 115 consecutive patients who underwent bilateral RLN lymphadenectomy during thoracoscopic McKeown esophagectomy for esophageal squamous cell carcinoma (ESCC) by a single surgeon between July 2017 and November 2023 were reviewed. The cohort was divided into three groups: Group 1 (initial 23 cases without IONM), Group 2 (middle 46 cases without IONM), and Group 3 (late 46 cases with IONM). We compared the number of resected lymph nodes and the incidence of vocal cord palsy (VCP) among the three groups. Results The mean number of resected right-side RLN lymph nodes was 1.21, 2.30, and 3.28 in Groups 1, 2, and 3, respectively. A significant difference was noted between Groups 2 and 3 (p = 0.03, Kruskal-Wallis test). The mean number of resected left-side RLN lymph nodes was 1.13, 2.70, and 2.67 in Groups 1, 2, and 3, respectively. A significant difference was noted between Groups 1 and 2 (p = 0.009), but not between Groups 2 and 3. The incidence of VCP was 8.7%, 8.7%, and 10.9% in Groups 1, 2, and 3, respectively. Compared to Group 2, the utilization of IONM in Group 3 did not reduce the postoperative VCP rate (OR: 1.280, 95% CI: 0.321-5.107). Conclusions With increasing experience, the number of resected RLN lymph nodes significantly increased. However, the utilization of IONM did not further improve left-side RLN lymphadenectomy or reduce the VCP rate.