Video Laryngeal Mask Airway for Visual Recurrent Laryngeal Nerve Monitoring in Thyroid Surgery

Objective: To evaluate the feasibility of a video flexible laryngeal mask airway (VFLMA) for simultaneous ventilation and direct visual RLN monitoring during thyroid surgery. Methods: This prospective single-arm study enrolled 104 consecutive patients undergoing thyroid surgery, in whom the VFLMA provided real-time glottic views after induction. The primary outcome was successful ventilation with RLN monitoring. Secondary outcomes included diagnostic performance of visual RLN monitoring (vocal cord movement upon stimulation) and perioperative respiratory adverse events. Results: Effective ventilation with RLN monitoring was achieved in 98 of 104 patients (94.2%). Six patients (5.8%) required conversion to endotracheal intubation with only 2 (1.9%) occurring during surgery. Among 137 monitored RLNs, loss of signal occurred in 7 (5.1%) and correlated with transient postoperative vocal fold palsy; observed sensitivity, specificity, and predictive values were 100% (95% CIs wide due to few events). Transient ventilatory disturbances occurred in 21.2% (elevated airway pressure), 8.7% (reflex laryngospasm), and 1.9% (transient air leakage) on ITT analysis (n = 104), all resolved with simple measures. Postoperative throat pain and odynophagia were mild and resolved within 1 week in most patients. Conclusions: In this exploratory feasibility study, the VFLMA enabled direct visual RLN monitoring during thyroid surgery with an acceptable ventilation success rate. These preliminary findings are hypothesis-generating and require validation in comparative studies. With appropriate patient selection, the VFLMA may offer an alternative approach for RLN monitoring. Trial Registration: The study was registered at www.chictr.org.cn (Identifier: ChiCTR2500105012). Level of Evidence: 4.