Outcomes of intraoperative nerve monitoring during esophagectomy: a systematic review and meta-analysis

Background Esophageal cancer is one of the leading causes of cancer-related deaths worldwide. The curative treatment done is an esophagectomy. A crucial element of this operation involves the dissection of the mediastinal lymph nodes, especially around the recurrent laryngeal nerve, due to the high likelihood of metastasis. As a result, the incidence of recurrent laryngeal nerve palsy remains a major postoperative complication. The study aims to evaluate the effectiveness of intraoperative nerve monitoring in reducing recurrent laryngeal nerve palsy in patients undergoing esophagectomy. Methods A meta-analysis was conducted including 12 articles identified via Pubmed, Scopus and Web of Science. Outcomes were calculated by using incidence of recurrent laryngeal nerve palsy, operative time, duration of hospital stay, mediastinal and total lymph node yield and other complications like anastomotic leak and postoperative pneumonia. Results There were no significant differences in operative time (WMD, 11.04; 95% CI, -10.88 - 32.86 p < 0.01), duration of hospital stay (WMD, -19.75; 95% CI, -40.72 - 1.23 p < 0.01), number of dissected lymph nodes (WMD, 1.24; 95% CI, -3.43 - 5.91 p < 0.01) or anastomotic leak (RR, 0.85; 95% CI, 0.62 - 1.18. p=0.63). However, the incidence of recurrent laryngeal nerve palsy (RR, 0.52; 95% CI, 0.39 - 0.71. p=0.01) and postoperative pneumonia (RR, 0.56; 95% CI, 0.45 - 0.70. p=0.21) was reduced. Conclusion Intraoperative nerve monitoring is found to reduce postoperative rates of recurrent laryngeal nerve palsy and postoperative pneumonia. There was no significant difference with respect to incidence of anastomotic leaks, number of lymph nodes dissected, operative time or duration of hospital stay.