Randomization and masking method
nerve block
BLIND
Random numbers were generated for each part using the SAS statistical package version 9.3 (SAS Institute, Cary, NC, USA) in a ratio of 1:1:1 with a block size of 6. Random numbers were enveloped in opaque bags and were allocated to participants in sequence before nerve block.Trial drugs (either remimazolam or normal saline) were colorless and were prepared with the same brand syringes by a designated nurse (J-M W) who did not take part in drug administration and outcome evaluation. Thus, blind method was kept to patients, researchers in charge of outcome assessment and other healthcare providers.