Background: Postoperative pulmonary complications may be reduced when neuromuscular block is reverted with sugammadex due to a lower incidence of residual block and to impairment of diaphragm function after neostigmine administration. 
Objectives: The aim of the study is to compare lung function after major abdominal surgery when reversal of neuromuscular blockade is carried out with sugammadex or neostigmine.
Design: A randomized controlled trial. 
Setting: A tertiary teaching hospital in Spain. 
Patients: Adults scheduled for major abdominal surgery under combined general and epidural anaesthesia with no contraindications for any of the study drugs. 
Interventions: Spirometry and lung ultrasound were performed before surgery and one hour and 24 hours postoperatively. Differences in mean changes from baseline were analyzed with repeated measures ANOVA.
Main outcomes measures: Forced vital capacity (FVC) loss, rate and size of atelectasis one hour after surgery in patients reverted with 40μg/kg of neostigmine versus 4mg/kg of sugammadex.
Results: One hundred and twenty-six patients were included for the main analysis. In the neostigmine group, basal FVC was 2.98 ± 0.13, IC95%(2.76 - 3.24) and one hour after surgery FVC was 2.5 ± 0.12, CI95%(2.27 - 2.74) In the sugammadex group basal FVC was 3.02 ± 0.13, CI95% (2.76 - 3.29) and decreased to 2.58 ± 0.12, CI95% (2.35 - 2.81) in the first hour. A total of 39.34% of patients in the neostigmine group and 29.51% in the sugammadex group had visible atelectasis. Mean size was 14.80 cm2 (CI95%: 6.58-22.03) and 8.0 cm2 (CI95%: 5.78-10.22), respectively. 
Conclusions: We could not find differences in pulmonary function after reversal with sugammadex or neostigmine in a high-risk population.
Trial Registration: Eudra-CT: 2014‐005156‐26


05 / Effects of neuromuscular block reversal with sugammadex versus neostigmine on postoperative respiratory outcomes after major abdominal surgery, a randomized controlled trial.