Recovery of Laryngeal Nerve Function With Sugammadex After Rocuronium-Induced Profound Neuromuscular Block

Tracheal intubation during routine and rapid-sequence intubation is facilitated by rocuronium, which is a nondepolarizing aminosteroid neuromuscular block (NMB) agent, higher doses of which (1.2 mg/kg) typically produces a complete neuromuscular blockade in less than 2 minutes that is long acting. Recovery from NMB and restoration of full control of pharyngeal and laryngeal muscles are important in airway maintenance and protection in surgical patients. Neuromuscular block can be accurately monitored using acceleromyography. Sugammadex, the first of a new class of selective muscle relaxant–binding drugs, is used to rapidly and effectively reverse NMB induced by aminosteroid neuromuscular-blocking drugs. Studies have looked at NMB reversal on various muscles, none of which correlate exactly with recovery of laryngeal muscles. An observational study was carried out to evaluate the efficacy of sugammadex in reversing rocuronium-induced NMB of laryngeal muscle function using neurophysiologic monitoring. Another aim of this study was to establish the time of recovery after 16 mg/kg of sugammadex using motor-evoked potentials (MEPs) compared with acceleromyography. All statistical tests were 2-sided with a significance level of 0.05, and the results were presented as the mean (continuous variables) ± SD or percentage (categorical variables). The test results showed that myogenicMEPs responses were absent, and neuromuscular monitoring showed a deep block in all patients (train-of-4 ratio of 0, posttetanic count of 1–2) at the time of sugammadex administration. It was also observed that the time to complete recovery of the basal myogenic MEPs amplitudes was 70 ± 18.2 at the laryngeal adductor muscles and 135 ± 14.1 seconds at the abductor digiti minimi. The value of the corresponding train-of-4 ratio was 0.7 ± 0.1. Incomplete neuromuscular recovery can cause respiratory impairment and hypoxemia in patients; hence, complete recovery of neuromuscular transmission at the laryngeal muscles is paramount for airway protection. This neurophysiologic study confirmed that administering 16 mg/kg sugammadex caused complete and effective recovery of laryngeal nerve function from rocuroniuminduced NMB. No adverse effects due to transcutaneous stimulation (such as cardiac arrhythmias and skin irritation) of the laryngeal nerve were observed, and no adverse effects due to sugammadex were noted.