Sugammadex and neostigmine given to reverse residual neuromuscular blockade can cause side effects including bradycardia, anaphylaxis, bronchospasm, and even cardiac arrest. We tested the hypothesis that sugammadex is noninferior to neostigmine on a composite of clinically meaningful side effects, or vice versa.
We analyzed medical records of patients who had general, cardiothoracic, or pediatric surgery and were given neostigmine or sugammadex from June 2016 to December 2019. Our primary outcome was a collapsed composite of bradycardia, anaphylaxis, bronchospasm, and cardiac arrest occurring between administration of the reversal agent and departure from the operation room. We a priori restricted our analysis to side effects requiring pharmacologic treatment that were therefore presumably clinically meaningful. Sugammadex would be considered noninferior to neostigmine (or vice versa) if the odds ratio for composite of side effects did not exceed 1.2.
Among 89,753 surgeries in 70,690 patients, 16,480 (18%) were given sugammadex and 73,273 (82%) were given neostigmine. The incidence of composite outcome was 3.4% in patients given sugammadex and 3.0% in patients given neostigmine. The most common individual side effect was bradycardia (2.4% in the sugammadex group versus 2.2% neostigmine). Noninferiority was not found, with an estimated odds ratio of 1.21 (sugammadex versus neostigmine; 95% confidence interval [CI], 1.09–1.34; noninferiority P = .57), and neostigmine was superior to sugammadex with an estimated odds ratio of 0.83 (0.74–0.92), 1-side superiority P < .001.
The composite incidence was less with neostigmine than with sugammadex, but only by 0.4% (a negligible clinical effect). Since 250 patients would need to be given neostigmine rather than sugammadex to avoid 1 episode of a minor complication such as bradycardia or bronchospasm, we conclude that sugammadex and neostigmine are comparably safe.