Reversal of Neuromuscular Blockade by Sugammadex after Continuous Infusion of Rocuronium in Patients Randomized to Sevoflurane or Propofol Maintenance Anesthesia

Background: Sugammadex rapidly reverses neuromuscular blockade induced by bolus rocuronium doses, but it has not been investigated after continuous rocuronium infusion in surgical patients. We therefore examined the clinical effect of sugammadex for neuromuscular blockade induced by continuous rocuronium infusion in adults undergoing surgery under maintenance anesthesia with sevoflurane or propofol. Methods: This four-center, comparative, parallel-group study, randomly assigned 52 adult patients (American Society of Anesthesiologists Class I-III) to maintenance anesthesia with sevoflurane or propofol. Neuromuscular blockade was induced by bolus injection of 0.6 mg/kg rocuronium followed by continuous infusion of 7 mu g . kg(-1) . min(-1) rocuronium adjusted to maintain a neuromuscular blockade depth of zero response to train-of-four and a posttetanic count of no more than 10 responses. A single dose of 4 mg/kg sugammadex was administered at first twitch (T-1) 3-10%. The primary clinical effect variable was recovery time to a train-of-four ratio of 0.9. Results: Median recovery time from start of sugammadex administration to a train-of-four ratio of 0.9 in the sevoflurane and propofol groups was 1.3 and 1.2 min, respectively. The estimated difference in recovery time between groups was 9 s (95% confidence interval -6 to 20 s), entirely within the predefined equivalence interval. Median plasma rocuronium concentration just before sugammadex administration was 33% lower during maintenance anesthesia with sevoflurane than with propofol. Sugammadex was well tolerated. One adverse event (procedural hypotension) was considered to be probably related to sugammadex. Conclusions: Single-dose sugammadex (4 mg/kg) after continuous rocronium infusion is equally effective and well tolerated during maintenance anesthesia with sevoflurane or propofol.