Changes in electromyographic amplitudes but not latencies occur with endotracheal tube malpositioning during intraoperative monitoring for thyroid surgery: Implications for guidelines.

Objectives/hypothesis: During intraoperative neural monitoring (IONM) in thyroid and parathyroid surgery, endotracheal (ET) tube migration can result in a decrease in vocalis electromyographic (EMG) amplitude without a concordant latency elevation during stimulation of the recurrent laryngeal nerve (RLN).

Study Design: Retrospective review.

Methods: Data were reviewed retrospectively for thyroid and parathyroid surgery patients with IONM of the laryngeal nerves from January 2015 to December 2015.

The electrophysiology of thyroid surgery: electrophysiologic and muscular responses with stimulation of the vagus nerve, recurrent laryngeal nerve, and external branch of the superior laryngeal nerve.

Objectives/hypothesis: Correlation of physiologically important electromyographic (EMG) waveforms with demonstrable muscle activation is important for the reliable interpretation of evoked waveforms during intraoperative neural monitoring (IONM) of the vagus nerve, recurrent laryngeal nerve (RLN), and external branch of the superior laryngeal nerve (EBSLN) in thyroid surgery.

Study Design: Retrospective chart review.

Methods: Data were reviewed retrospectively for thyroid surgery patients with laryngeal nerve IONM from January to December, 2015.