2.1.4. Randomization and Blinding
The computer random number method generated a total of 113 random numbers (ranging from 1 to 113). The first 56 numbers were assigned to the CPVB group, and the remaining 57 digits were assigned to the CWI group. Patients ranked the numbers sequentially according to the experiment, and statistical analysis was finally performed based on the grouped information. Surgeries were performed by the same group of surgeons. The patients, data collector, and care team were blinded, while the anesthesiologists and surgeons were unblinded participants who were not otherwise involved in the study.