Supramaximal neurostimulation with laryngeal palpation to predict postoperative vocal fold mobility

• Published in: The Laryngoscope Vol. 126; no. 12; pp. 2863 - 2868
• Main Authors: Cha, Wonjae, Cho, Ilyoung, Jang, Jeon Yeob, Cho, Jae-Keun, Wang, Soo-Geun, Park, Ji-Hwan
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01-12-2016; Wiley Subscription Services, Inc
• Subjects: Adult; Aged; Aged, 80 and over; Electric Stimulation - methods; Female; Health risk assessment; Humans; Male; Middle Aged; Parathyroidectomy - adverse effects; Postoperative Complications - diagnosis; Postoperative Complications - etiology; predictive value; Predictive Value of Tests; Prospective Studies; recurrent laryngeal nerve; Recurrent Laryngeal Nerve - physiology; Recurrent Laryngeal Nerve Injuries - diagnosis; Recurrent Laryngeal Nerve Injuries - etiology; Supramaximal neurostimulation; Thyroid gland; thyroid surgery; Thyroidectomy - adverse effects; Vocal Cord Paralysis - diagnosis; Vocal Cord Paralysis - etiology; vocal fold palsy; predictive value; Supramaximal neurostimulation; recurrent laryngeal nerve; thyroid surgery; vocal fold palsy
• ISSN: 0023-852X; 1531-4995
• DOI: 10.1002/lary.26011

Objectives/Hypothesis
Recurrent laryngeal nerve (RLN) injury during thyroidectomy or parathyroidectomy is a challenging issue and causes significant morbidity. We adopted the supramaximal stimulation protocol for neurostimulation with laryngeal palpation (NSLP) and tried to evaluate the predictive values of supramaximal NSLP for immediate postoperative vocal fold (VF) mobility.
Study Design
Prospective cohort study.
Methods
Prospectively, 293 patients who underwent thyroid and parathyroid surgery and 542 RLNs at risk were enrolled in this study. During NSLP, the current was escalated to 3 mA until definite laryngeal twitch was observed. Immediate postoperative VF mobility was evaluated using flexible laryngoscopy.
Results
Diagnostic accuracy of NSLP is calculated according to cutoff values of minimal current intensity (1 mA, 1.5 mA, and 2 mA). At 2mA, sensitivity was 81.82%, specificity 100%, positive predictive value 100%, and negative predictive value 99.62%.
Conclusions
Supramaximal NSLP might be a simple and reliable method to predict immediate postoperative VF mobility in open thyroid and parathyroid surgeries when intraoperative neuromonitoring is unavailable.
Level of Evidence
4. Laryngoscope, 126:2863–2868, 2016