2.1. Ethics approval and patient selection
allergy
ALLERGY
This was a prospective study and was approved by the Institutional Ethics Committee of Hainan Wanning People’s Hospital (SL-2021-002). The inclusion criteria were as follows: (1) American Society of Anesthesiologists Class I to III, aged ≥ 18 years; (2) normal liver and kidney function; (3) undergoing open or laparoscopic lower abdominal or pelvic surgery; and (4) no history of allergy to the drugs used in this study. Patients or their families provided written informed consent before the trial and could withdraw from the trial at any stage. All methods were performed in accordance with the relevant guidelines, regulations, and CONSORT recommendations. This trial was registered with 