Efficacy and Safety of Anrikefon Injection for the Treatment of Postoperative Pain in Patients Undergoing Laparoscopic Hepatectomy

1. Age between 18 and 75 years, any gender;
2. American Society of Anesthesiologists (ASA) score of I or II;
3. BMI between 18 kg/m² and 30 kg/m²;
4. Patients scheduled for laparoscopic liver resection under general anesthesia, with surgery lasting less than 6 hours;
5. Surgical incision less than 10 cm;
6. Able to understand pain intensity assessment methods.

Participants understand the purpose and procedures of this study, voluntarily participate, and sign a written informed consent form.

Exclusion Criteria:

1. Patients allergic to opioids, flurbiprofen ester, or any other ingredients in the investigational drugs.
2. Patients expected to use continuous epidural analgesia or local block analgesia during the treatment period.
3. Patients with a history of gastrointestinal ulcers or bleeding who need treatment.
4. Patients undergoing emergency surgery or trauma.
5. Patients whose surgery needs to be converted to open abdominal surgery.
6. Patients unwilling to use patient-controlled intravenous analgesia (PCIA).
7. Patients with a history of upper abdominal surgery.
8. Patients expected to require postoperative continued intubation.
9. Patients needing postoperative admission to the ICU.
10. Patients with any of the following disease history or evidence before screening:
11. Severe cardiovascular or pulmonary diseases (myocardial infarction, heart failure, or respiratory failure).
12. Neurological or psychiatric history: brain injury, intracranial hypertension, schizophrenia, mania, etc., judged by the investigator as not suitable for the study.
13. History of digestive diseases: intestinal obstruction or other digestive system diseases that may cause nausea or vomiting as judged by the investigator; accompanied by other severe digestive tract issues affecting digestion (e.g., severe constipation, duodenal stasis syndrome, etc.), or other digestive diseases evaluated by the investigator as unsuitable for the study.
14. Patients with obvious chronic dizziness or diagnosed vestibular function disorders (other than motion sickness), including but not limited to peripheral vestibular syndrome or central vestibular syndrome.
15. Patients who received neoadjuvant treatment before surgery.
16. Patients who experienced nausea, retching, or vomiting within 24 hours before anesthesia induction (excluding bowel prep-related cases).
17. Known allergy or contraindication to other anesthetics or antiemetics that may be used during the trial.
18. Patients who used drugs with unclear half-lives that have analgesic or antiemetic effects within 14 days before randomization, or whose last use was less than 5 half-lives or the drug's effective duration (whichever is longer), including but not limited to opioids, non-opioid analgesics, antiemetics (or drugs with antiemetic effects), sedatives, anesthetics, corticosteroids, and other similar drugs.
19. Patients needing dialysis or who have alcoholism during treatment.
20. Pregnant or breastfeeding women, or those planning pregnancy during the study period or within 3 months after study completion.
21. Subjects the investigator believes have any other factor making them unsuitable for this clinical study.