The dose of sugammadex recommended by the manufacturer for reversal of rocuronium is 2 mg/kg when the train-of-four count is 2 or more and 4 mg/kg when it is less than 2 but there is a posttetanic count of at least 1. The purpose of this dose-finding study was to titrate sugammadex to produce a train-of-four ratio 0.9 or greater at the conclusion of cardiac surgery, and to continue monitoring neuromuscular blockade in the intensive care unit to identify recurrent paralysis. The hypothesis was that many patients would require less than the recommended dose of sugammadex, but that some would require more, and that recurrent paralysis would not occur.
Neuromuscular blockade was monitored using electromyography during cardiac surgery. Administration of rocuronium was at the discretion of the anesthesia care team. During sternal closure, sugammadex was titrated in 50-mg increments every 5 min until a train-of-four ratio 0.9 or greater was obtained. Neuromuscular blockade was monitored with electromyography in the intensive care unit until sedation was discontinued before extubation or for a maximum of 7 h.
Ninety-seven patients were evaluated. The dose of sugammadex required to achieve a train-of-four ratio of 0.9 or greater varied from 0.43 to 5.6 mg/kg. There was a statistically significant relationship between the depth of neuromuscular blockade and the sugammadex dose required for reversal, but there was a large variation in dose required at any depth of neuromuscular blockade. Eighty-four of 97 patients (87%) required less than the recommended dose, and 13 (13%) required more. Two patients required additional sugammadex administration for recurrent paralysis.
When sugammadex was titrated to effect, the dose was usually less than the recommended dose, but it was more in some patients. Therefore, quantitative twitch monitoring is essential for ascertaining that adequate reversal has taken place after sugammadex administration. Recurrent paralysis was observed in two patients.
- Sugammadex is effective for reversing neuromuscular blockade produced by rocuronium or vecuronium
- The manufacturer has recommended that a sugammadex dose of 2 mg/kg be administered if at least two twitches are present in response to a train-of-four stimulus, or 4 mg/kg if there are less than two twitches but a posttetanic count of more than 0
- The hypothesis that many patients would require less than the recommended dose of sugammadex, but that some would require more, and that recurrent paralysis would not occur was tested in a prospective dose-finding study of 97 cardiac surgery patients administered rocuronium in whom neuromuscular blockade was monitored using an electromyography-based twitch monitor
- The sugammadex dose required for an individual patient could not be predicted with certainty based on the train-of-four twitch response immediately before reversal
- Two patients had recurrent paralysis during the postoperative monitoring period
- Quantitative twitch monitoring is essential to evaluate the effectiveness of reversal with sugammadex