Statistical analysis
A sample size was calculated based on the primary outcome variable (the time from the administration of neostigmine to a TOF ratio of 0.9). To achieve a power of 0.8 with an alpha level of 0.05 and an effect size of f = 0.25, and considering a 10% drop out rate, a total sample size of N = 200 was needed. SPSS 22.0 software was used for statistical analysis. Count data were expressed as composition ratio; normally distributed measures were expressed as mean ± standard deviation, and t-test was used for comparison between two groups and one-way ANOVA for comparison between multiple groups; non-normally distributed measures were expressed as median (interquartile range), and Kruskal-Wallis H rank sum test was used for comparison between multiple groups; while categorical data were expressed as numbers with percentages and were compared using the Chi-square test. 