Perioperative Mirogabalin for Pain Relief After Modified Radical Mastectomy

This study aims to evaluate whether perioperative mirogabalin can reduce postoperative pain and morphine consumption in female patients undergoing modified radical mastectomy for breast cancer. Postoperative pain is common after breast cancer surgery and may increase the need for opioid medications such as morphine. Although mirogabalin has been used to treat certain types of nerve pain, evidence regarding its effectiveness for acute postoperative pain remains limited. This prospective, randomized, double-blind, placebo-controlled study will include 50 female patients aged 18-65 years with American Society of Anesthesiologists (ASA) physical status II or III who are scheduled for elective modified radical mastectomy at the National Cancer Institute, Cairo University. Participants will be randomly allocated to one of two groups. The mirogabalin group will receive 15 mg orally approximately 2 hours before surgery and every 12 hours for 48 hours after surgery. The control group will receive matching placebo capsules on the same schedule. Both groups will receive standardized general anesthesia and multimodal postoperative analgesia, including paracetamol and ketorolac, when appropriate. Intravenous morphine will be administered as rescue analgesia according to a predefined protocol when the postoperative pain score reaches 4 or higher on a 0-10 visual analogue scale. The primary outcome will be total intravenous morphine consumption during the first 24 hours after surgery. Secondary outcomes will include postoperative pain scores at rest and during movement, time to first rescue analgesia, the number of patients requiring morphine, postoperative nausea and vomiting, sedation, dizziness, respiratory safety, hemodynamic changes, recovery from anesthesia, patient satisfaction, and quality of recovery. The study will assess whether adding mirogabalin to standard multimodal analgesia improves postoperative pain control and reduces opioid requirements without unacceptable adverse effects. The findings may help clarify the potential role of mirogabalin in perioperative pain management for patients undergoing breast cancer surgery.