Postoperative oxygenation assessed by SpO2/FiO2 ratio and respiratory complications after reversal of neuromuscular block with Sugammadex or neostigmine: A retrospective cohort study

Abstract

Study objectiveResidual neuromuscular block may lead to postoperative muscle weakness, inadequate oxygenation, and other pulmonary complications. Sugammadex may provide more rapid and effective restoration of neuromuscular function than neostigmine. We therefore tested the primary hypothesis that noncardiac surgical patients given sugammadex oxygenate better during initial recovery than those given neostigmine. Secondarily, we tested the hypothesis that patients given sugammadex have fewer pulmonary complications during hospitalization. DesignRetrospective cohort analysis. SettingPostoperative recovery area of a tertiary care hospital. PatientsAdults who had non-cardiothoracic surgery and were given either neostigmine or sugammadex. InterventionsNone. MeasurementsThe primary outcome was the lowest SpO2/FiO2 ratio in the post-anesthesia care unit. The secondary outcome was a composite of pulmonary complications. Main resultsAmong 71,457 cases, 10,708 (15%) were given sugammadex and 60,749 (85%) received neostigmine. After propensity weighting, the mean minimum SpO2/FiO2 ratio was 301 ± 77 (SD) in patients given sugammadex and 303 ± 71 in those given neostigmine, yielding an estimated difference in means of −3.5 (95% confidence interval: −5.3, −1.7; P = 0.0002). 4.4% of patients given sugammadex and 3.6% of patients given neostigmine had postoperative pulmonary complications (P = 0.0005, number-needed-to-be-exposed =136; 95% CI: 83, 330), with the main contributing components being new bronchospasm or exacerbation of obstructive pulmonary disease. ConclusionsPostoperative minimum SpO2/FiO2 ratio during PACU admission was similar after reversal of neuromuscular block by sugammadex and neostigmine. Reversal with sugammadex was associated with more pulmonary complications, but most were minor and of little consequence.