Clinical Research Directory

Inclusion Criteria: * ASA I\~III； * BMI ranging from 18 to 28 kg/m²； * For elective laparoscopic-assisted major abdominal surgery under general anesthesia; * Estimated surgical duration (from incision to the last suture of the skin) was at least 2 hours. Exclusion Criteria: * Pregnant or lactating patients; * Patients diagnosed with septic shock or multiple organ failure within 14 days; * Patients with preoperative severe electrolyte disorders; * Patients with stroke, transient ischemic attack, or other similar events within the past 3 months * Patients with unstable angina, myocardial infarction within the past 3 months; or presence of untreated arrhythmia or arrhythmia not well-controlled with treatment; * Patients with diabetes, uncontrolled blood glucose levels, or diabetes complications such as diabetic ketoacidosis, hyperosmolar coma, diabetes-related infections, diabetic nephropathy, retinopathy, diabetic cardiomyopathy, diabetic peripheral neuropathy, diabetic foot, etc. before the surgery; * Patients with severe liver dysfunction (Child-Pugh score \> 6), renal dysfunction (GFR \< 90 ml/(min•1.73m²)); * Exploratory surgeries, day surgeries, or surgeries that only involve opening and closing the abdomen; * Blood pressure ≥180/110 mmHg at rest (≥Grade 3 hypertension according to the 2020 ISH Hypertension Guidelines); or systolic blood pressure \<90 mmHg or mean blood pressure \<65 mmHg; * Patients participated in other drug trials within the past 3 months; * Patients with communication difficulties, inability to understand pain scores or patient-controlled intravenous analgesia; * Patients with consciousness disorders or other psychiatric illnesses; * Patients with a confirmed or suspected history of substance abuse or long-term use of anesthetic sedatives and analgesics; * Cancer patients have received neoadjuvant treatment or chemotherapy preoperatively; * Allergic to the drugs used in this trial and their components.