Sample size calculations
The main aim of this study was to compare the first FICB times. Based on the results of the pretest, we assumed that the first FICB timepoint for the test group was 3.0 h and that for the control group was 4.0 h, both with a standard deviation of 1.5. To obtain a statistical power of 90% (β = 0.1) with a two-sided confidence interval of 95% (α = 0.05), we used PASS11 for calculations with a sample size of 80 patients (40 in each group). The study planned to recruit an additional 10% of patients to account for potential loss to follow-up and withdrawals.