Loss of signal (LOS) at intraoperative nerve monitoring (IONM) is defined as an >100 mV amplitude decrease and a >10% latency reduction and represents a predictor of postoperative impaired vocal cord motility (VCM). We aimed to evaluate if an intraoperative signal recovery (ISR) after LOS may predict a positive outcome of VCM. Among 5884 consecutive intermittent IONM-guided thyroidectomies (April 2021- March 2025) all the patients in whom a LOS was observed were evaluated. Topic and intravenous corticosteroids were administered to all of them. Eventual recovery was evaluated after 20 minutes. Patients with an ISR less than 50% compared to the baseline were included. The rate of vagal signal (VS) ISR was defined as a percent from the minimum value: VS-recovery-VS-minimal/VS-predissection-VS-minumum. ISR was correlated to VCM (ROC curve analysis). Among 169 patients with LOS, 65 (38.5%) showed ISR, with 48 (73.8%) of them exhibiting normal VCM on postoperative day 1 (POD-1). The remaining 17 patients with impaired VCM on POD-1 recovered normal VCM on POD-15 (7-10.8%) or POD-30 (10-15.4%). The AUC for impaired VCM at POD-1 was 0.938 (95% CI: 0.849-0.983, p 31% showed normal VCM. All patients with ISR 31% is associated with normal postoperative VCM and staged thyroidectomy could be avoided in this subgroup of patients with LOS.
Gallucci et al. (Wed,) studied this question.