Anesthesia and surgery
All patients in our study received general anesthesia involving induction with midazolam (0.02–0.03 mg/kg), propofol (1–2 mg/kg), sulfentanyl (0.3–0.5 μg/kg), and rocuronium (0.6–1.0 mg/kg), which were delivered by intravenous bolus injection. Exceptions were patients older than 60 years, who did not receive midazolam. Anesthesia was maintained through continuous intravenous infusion of remifentanil (0.1–0.2 μg/kg·min) and continuous inhalation of sevoflurane. Rocuronium was added every 40–60 min at 25–33% of the induction dose. Sulfentanyl (5ug) was added every hour.Intraoperative blood pressure was recorded every 3 min using an electrocardiogram and an upper-arm sphygmomanometer. Intraoperative blood pressure was maintained at baseline in the tourniquet group, or at approximately 70% of baseline in the non-tourniquet group. The target blood pressure was achieved through intravenous injection of m-hydroxylamine, ephedrine, and nicardipine.All patients received antibiotics at 0.5–2 h before surgery. At 10 min before surgery, all patients received intravenous dexamethasone (10 mg) and intravenous tranexamic acid (60 mg/kg). Previous studies have confirmed the efficacy and safety of a preoperative high-dose (60 mg/kg) combined with postoperative multiple-dose tranexamic acid sequential application regimen [