Laryngeal mask anesthesia with intraoperative laryngoscopy for identification of the recurrent laryngeal nerve during thyroidectomy

Abstract

Objectives/hypothesis: A critical step in thyroidectomy involves definitive identification of the recurrent laryngeal nerve (RLN). Using the laryngeal mask airway, identification of the RLN can be facilitated by stimulation of the nerve while monitoring vocal cord movement with a fiberoptic laryngoscope. We present this technique as an effective and safe means to identify the RLN during thyroid surgery, with significant advantages over existing techniques in appropriately selected patients.

Study design: Retrospective case series.

Methods: We performed thyroidectomy on 8 patients (13 RLN identifications) in which laryngeal mask airway anesthesia with fiberoptic laryngoscopy was used to identify the RLN. Results are reviewed with regard to postoperative vocal cord function, as well as intraoperative and postoperative courses with laryngeal mask airway anesthesia.

Results: In all 13 cases in which the RLN was sought, it was definitively identified by witnessing brisk vocal cord movement on a video screen with stimulation of the RLN. No patient had postoperative vocal cord paresis or paralysis. Overall recovery from laryngeal mask airway anesthesia was uneventful and had advantages when compared with general anesthesia with endotracheal intubation.

Conclusions: Laryngeal mask airway anesthesia with intraoperative fiberoptic laryngoscopy to identify the RLN is effective and safe in carefully selected patients. Advantages include decreased postoperative throat discomfort, absence of coughing during emergence from anesthesia, and elimination of the possibility of vocal cord mobility impairment secondary to RLN ischemia from the endotracheal tube balloon. In addition, this technique is applicable in operations besides thyroid surgery, in which definitive identification of the RLN is indicated.