Postoperative analgesia protocol and rescue analgesic
NRS
Following the surgical procedure, patients were admitted to the post-anesthesia care unit (PACU) and subsequently transferred to the ward upon stabilization of vital signs. All patients received the same postoperative multimodal analgesia regimen, which included intravenous administration of ketorolac tromethamine 30 mg every eight hours and patient-controlled neural analgesia (PCNA) after surgery. The PCNA formula consisted of 0.10% ropivacaine (300 ml), and the parameters for PCNA was set as follows: continuous infusion dose of 5 ml/h, bolus dose of 5 ml, lock time of 30 min, and continuous analgesia for 48 h. In cases where the NRS was ≥ 4 points and persisted for more than 30 min, intravenous rescue analgesia was administered using oxycodone hydrochloride at a dose of 0.1 mg/kg.