Clinical Research Directory

Inclusion Criteria: 1.Preoperative inclusion criteria 1. aged ≥18 years and ≤75 years at screening; 2. Plan to undergo open or laparoscopic abdominal surgery, and the estimated operative time more than 2 hours. 3. able to understand and comply with research procedures and requirements, and can provide a written informed consent. 2.postoperative inclusion criteria: 1. patients who required open or laparoscopic surgery; 2. According to the investigator's judgment, the patient had recovered sufficiently from the intraoperative anesthesia protocol to accurately complete the protocol-specified questionnaire; Exclusion Criteria: 1.preoperative exclusion criteria: 1. ASA grade \>III 2. existing other acute or chronic pain conditions; 3. body mass index (BMI) \< 18 or \> 30 kg/m2; 4. with sleep apnea syndrome; 5 ) long-term opioid treatment, defined as receiving more than 15mg morphine equivalent units per day on more than 3 days per week for a period of more than 1 month in the 12 months prior to surgery; 6\) suffering from mental or nervous system diseases (such as epilepsy, depression, schizophrenia, etc.), chronic obstructive pulmonary disease or pulmonary heart disease, heart failure, severe arrhythmia, etc; 7) with severe liver and kidney dysfunction; 8) Other conditions considered by the investigator to be inappropriate for enrollment. Postoperative exclusion criteria: 1. intraoperative, postoperative or anesthetic deviations that may affect the efficacy and safety evaluation in the study; 2. evidence of hemodynamic instability or respiratory insufficiency.