Intraoperative Neuromonitoring of the Recurrent Laryngeal Nerve in Thyroid Surgery

Inroduction: Monitoring of the recurrent laryngeal nerve (RLN) has been claimed in some studies to reduce rates of nerve injury during thyroid surgery compared with anatomical dissection and visual identification of the RLN alone, whereas its role has not been well established. This study evaluates whether RLN injury can be reduced by the application of this technique during thyroidectomy. Methods: Of 240 RLN that were at risk of injury in 130 consecutive patients who underwent thyroidectomy with the use of neuromonitoring (continuous monitoring with endotracheal electrodes) was compared with that of 1,211 RLN, in 664 patients that were operated by routine identification only. The incidences of RLN paralysis were compared between the 2 groups. Results: Postoperative palsy was identified in 13 recurrent laryngeal nerves in the group with the use of neuromonitoring (5.4%). While 36 recurrent laryngeal nerves palsy was identified in the group without the use of neuromonitoring (3%). There was no significant difference in postoperative, transient, and permanent paralysis rates between the neuromonitoring and control groups. The sensibility, the specificity, the accuracy and Positive Predictive Value and Negative Predictive Value of neuromonitoring were rispectly 66.7, 97.8 e 95.7, 66.7, 97.8% compared with neurostimulation that were rispectly 66.7, 96.7, 95.1, 52.8, 98.1%. Discussion: Neuromonitoring of the RLN during thyroid surgery could not be demonstrated to reduce RLN injury significantly, compared with the adoption of routine RLN identification. However, its application can be considered for selected high-risk thyroidectomies.