Study treatments
bradycardia, Hypertension, Hypotension, tachycardia
HYPERTENSION
All patients in this study were admitted on the day of surgery and discharged on the first day after surgery, during which one overnight stay was required. The patients received routine preoperative preparation and no premedication was administered. Standardized vital signs monitoring, including noninvasive BP monitoring, ECG, pulse oxygen saturation (SpOThe non-invasive BP monitoring instrument regularly measured the patient's BP every 5 min; ECG continuously monitored the patient's HR. When the measured BP fluctuated more than 20 per cent of the baseline level, the BP was measured again immediately. If it still fluctuated more than 20 per cent of the baseline level, sufentanil (5–10 μg) was given. The BP was measured again 5 min after sufentanil was given. If the BP fluctuation was lower than 20 per cent of the baseline level, the haemodynamic changes were continuously monitored and observed. No additional sufentanil was used during the surgery. Hypotension (the BP was decreased by more than 20 per cent of baseline) was treated with ephedrine (0.6 mg) and bradycardia (HR of < 45 beats/min) with atropine (0.5 mg). Hypertension (SBP > 150 mmHg) was treated with nicardipine (5 μg/kg) and tachycardia (HR > 90 beats/min) with esmolol (0.3 mg/kg).Ten minutes before tourniquet inflation, the L group was administered a single-dose IVL with a concentration of 1.6 per cent lidocaine (1.5 mg/kg), diluted to 10 ml with 0.9 per cent normal saline, with an administration rate of 1 ml/s. The N group was injected with 10 ml 0.9 per cent normal saline intravenously at the same time.Afterwards the surgeon placed the tourniquet on the upper thigh of the operative side, raised the limb to 45°, then used an elastic bandage to help reduce the amount of blood accumulated in the leg. The tourniquet cuff was then inflated by the surgeon to 250 mmHg. After the tourniquet was inflated, the surgeons immediately performed a skin cutting surgery (the surgery began); the tourniquet was deflated immediately after the skin suture (the surgery ended). Therefore, the duration of tourniquet inflation was equal to the duration of surgery. Remifentanil infusion was stopped at the end of the skin suture and the propofol infusion was stopped after the tourniquet was deflated.After the surgery, each patient was administered 50 mg flurbiprofen axetil for analgesia, then sent to PACU. When autonomous breathing was regular, tidal volume was > 6 ml/kg, SpO