Maintenance of anesthesia
MUSCLE RELAXATION
A total of 1% sevoflurane was administered intraoperatively, with an inhalation oxygen flow rate of 2 L/min, and the patient’s BIS value was maintained at 45–55 by adjusting the effective chamber target concentration of propofol (± 0.5 μg/ml, up to 3.5 μg/ml). The target concentration of the effective chamber of remifentanil was adjusted to 1.5–4.0 ng/ml, and the fluctuation of the mean arterial pressure (MAP) was maintained at no more than ± 20% of the baseline value. When necessary, 5 μg of sufentanil was injected intravenously, and an intermittent intravenous injection of 5 mg of cisatracurium was administered to maintain muscle relaxation. The respiratory parameters were adjusted to maintain the partial pressure of end-tidal carbon dioxide at 35–40 mmHg. The inhalation of sevoflurane was stopped 10 min before the end of surgery, and the intravenous general anesthetic was terminated 5 min before the end of surgery.