Preventive Analgesia With Anrikefon in Laparoscopic Cholecystectomy

Effect of Preventive Analgesia With Anrikefon on Postoperative Acute Pain and Rehabilitation Process in Adult Patients Undergoing Laparoscopic Cholecystectomy

This study will determine the optimal timing for Anrikefon administration. It will also assess the quality of patient recovery. Laparoscopic cholecystectomy (LC) is a routine surgical procedure. However, the incidence of acute visceral and incision pain is high, reaching 50% to 70%. This pain significantly impairs patient recovery.

Anrikefon is novel peripherally restricted κ-opioid receptor agonist. It has very low brain penetration. This property reduces central nervous system side effects and respiratory depression. Preventive analgesia blocks the transmission of nociceptive stimuli to the central nervous system. It reduces postoperative pain sensitization and intensity. Currently, research on Anrikefon for preventive analgesia in LC patients is limited. It impacts on the recovery process is not yet fully understood. This study will compare drug administration before anesthesia induction with intra-operative administration.

Participants will be assigned to one of two groups with equal probability using computer-generated random numbers. Patients in the Preventive Analgesia group will receive Anrikefon injection 15 minutes before anesthesia induction. Bridging Analgesia group is the control group. Patients in this group will receive Anrikefon immediately after the gallbladder is detached from the liver. Both groups will receive the identical drug dosage of 1 μg/kg.

Both treatment groups will receive identical care beyond the time of Anrikefon administration. All patients will undergo standardized anesthesia management. Parecoxib sodium 40 mg will be injected for rescue analgesia if NRS score > 4. We will analyze the primary, secondary, and exploratory outcome measures after surgery, aiming to explore the optimal timing of Anrikefon and its impact on the patient's recovery process.

This study is a prospective, double-blinded, randomized controlled study. Adult patients (18-65 years old) who are planning to receive Laparoscopic Cholecystectomy will be enrolled into this study, and will be randomly divided according to 1:1. They will be named the preventive analgesia group and the bridging analgesia group. Primary end point is the time-weighted sum of pain intensity differences over 0-24 hours postoperatively (SPID₀-₂₄h) , which will be calculated according to the NRS scores at every time point(after surgery immediately ,15 minutes, 30 minutes, 1 hour, 2 hours, 4 hours, 8 hours, 12 hours, 16 hours, 20 hours, and 24 hours).

Inclusion Criteria:

1. ASA physical status classification I-III;
2. Age 18-65 years;
3. Scheduled for elective laparoscopic cholecystectomy;
4. Voluntary signed informed consent;
5. BMI between 18-28 kg/m²;
6. No history of general anesthesia surgery within the past 3 months.

Exclusion Criteria:

1. Severe cardiovascular disease, respiratory disease, or psychiatric disorders;
2. Severe renal insufficiency;
3. Recent use of diuretics or compound medications containing diuretics;
4. Continuous use of opioid analgesics for more than 10 days within the past 3 months;
5. Use of medications with unknown half-life affecting analgesic efficacy within 14 days prior to randomization;
6. Pregnant women, lactating women, or those planning pregnancy in the near future;
7. History of hypersensitivity to study medications.