Overview

The goal of this clinical trial is to learn if Anrikefon works as well as nalbuphine to control postoperative pain in adults undergoing ophthalmic surgery under general anesthesia. It will also learn about the safety and recovery outcomes of using Anrikefon.

The main questions it aims to answer are:

• Does Anrikefon provide pain relief that is not inferior to nalbuphine after ophthalmic surgery?
• Does Anrikefon cause fewer central side effects, such as sedation or dizziness, compared with nalbuphine?
• Does Anrikefon help patients recover and get discharged faster after day-surgery procedures? Researchers will compare Anrikefon to nalbuphine to see if Anrikefon can offer effective and safer perioperative analgesia for ophthalmic day-surgery patients.

Participants will:

• Receive either an intravenous dose of Anrikefon or nalbuphine during surgery.
• Be monitored for pain scores, side effects, and recovery parameters after surgery.
• Complete follow-up assessments.

Eligibility

Inclusion Criteria:

• Scheduled for ophthalmic surgery under general anesthesia.
• Aged 18 to 70 years.
• With American Society of Anesthesiologists (ASA) physical status I to III.
• Body mass index (BMI) between 18 and 30 kg/m²
• Agree to participate in the trial and provide written informed consent.

Exclusion Criteria:

• History of cardiovascular or cerebrovascular events within the past 6 months, including unstable angina, ischemic myocardial infarction, or heart failure; or current presence of uncontrolled hypertension (\>180/110 mmHg), aneurysm, or severe cardiac arrhythmia.
• Severe respiratory diseases such as pulmonary fibrosis, severe pulmonary abscess, cor pulmonale, or advanced chronic obstructive pulmonary disease (COPD).
• Significant neurological disorders such as brain injury or seizures, as well as severe psychiatric illnesses.
• Known allergy to kappa opioid receptor agonists or to general anesthetic agents used in this study.
• Current peptic ulcer disease, gastrointestinal bleeding, or known hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs), such as flurbiprofen axetil or paracetamol.
• Prior use of opioid or non-opioid analgesics, with the last administration occurring within five half-life periods of the drug.
• Continuous use of opioid analgesics for more than 10 days within the 3 months prior to screening.
• Use of drugs with unknown half-life periods that may affect analgesic efficacy within 14 days before randomization.
• History of major surgery within the past 3 months that may interfere with postoperative pain assessment.