Grouping
Statistical Analysis System (SAS, USA) software was used to generate the random sequence numbers for grouping, and the patients were divided into groups I or II at a ratio of 1:1, with 74 cases in each group. The grouping information was sealed in envelopes and randomly distributed to the subjects. The envelopes were opened by nurses on the day of surgery to check the random serial numbers and inform the anesthesiologists, all of whom had more than 10 years of clinical experience. The patients in group I received adhesive tape fixation at the periportal end of the DLT, while those in group II remained unfixed.