Postoperative recurrent laryngeal nerve palsy in thyroidectomy is a complication that must be avoided because it impairs speech and the swallowing function. The incidence is reported to be 3.0%-14.6% for postoperative recurrent nerve palsy and 0.7%-5.3% for permanent postoperative recurrent nerve palsy, so it is essential to understand the risk before surgery. In this study, we analyzed the incidence of postoperative recurrent laryngeal nerve palsy in our hospital and the associated patient, disease, and surgical factors to obtain a better clinical index for preventing postoperative recurrent laryngeal nerve palsy. There were 164 patients/217 sides (73 benign cases [45%], 91 malignant cases [55%]) who underwent thyroidectomy at our hospital from April 2018 to December 2019. Postoperative recurrent laryngeal nerve palsy was observed in 22 patients (10.1%), of whom 9 (4.1%) had permanent palsy. There were significant differences in the rate of postoperative recurrent laryngeal nerve palsy based on the preoperative fine-needle aspiration (FNA) class (P<0.01), N classification (P<0.01), surgical procedure (unilateral/total thyroidectomy) (P<0.01), presence of dissection (P<0.01), operative time (P=0.01), amount of bleeding (P=0.02), and presence of adhesions (P=0.05). For permanent palsy, there were significant differences in the preoperative FNA class (P<0.01), surgical form (unilateral/total) (P=0.03), and presence of dissection (P=0.01). In the case of benign lesions, a cut-off value of 100 mm for the tumor diameter was associated with postoperative recurrent laryngeal nerve palsy (P=0.01). Continuous intraoperative nerve monitoring should thus be considered for these high-risk cases.
