Anaesthesia protocol and extubation
TOF, residual neuromuscular block
All the patients received standardized monitoring procedures after entering the operation room: electrocardiography, the saturation of haemoglobin with oxygen, non-invasive blood pressure and bispectral index (BIS). The patients were induced with sufentanil 0.4 μg kgDuring recovery from general anaesthesia in PACU, sputum around the airway and endotracheal tube cuff could be suctioned when the patients were still under deep anaesthesia. No medications were given except neostigmine and atropine to antagonize residual neuromuscular block before extubation. Once the patients conformed to the indications of extubation (train of four ratio (TOF) was ≥ 0.9, EtCOAll the patients received patient-controlled intravenous analgesia postoperatively: sufentanil 50 μg; dexmedetomidine 200 μg and ondansetron 8 mg diluted to 100 ml with 0.9% sodium chloride. The dose was controlled at 1.5 ml at all times, the rate was 2 ml h 