Smooth extubation process can reduce the complications in recovery time. This study aimed to investigate what is the better time to extubation when children is breathing spontaneously and adequately: waiting until children have movements or wakefulness (passive extubation）or removing endotracheal tube directly (proactive tracheal extubation).

This is a randomized, controlled cross-over trial. The hypothesis of this study is that the different extubation protocol can impact recovery quality in children in post-anaesthesia care unit (PACU). Patients aged 3-7 years were randomized into two equal groups: proactive extubation (Group A) and passive extubation. At the end of surgery, sevoflurane was turned off and patients all delivered into PACU for recovery. Patient was positioned on his or her lateral side. The ventilation was switched to positive airway pressure (CPAP) mode once the patients regained spontaneous respiration. After spontaneous breathing turn to regular and sufficient（tidal volume >6-8 ml/kg, respiratory rate >10 times per minutes , end tidal carbon dioxide concentration >7.19 mmHg）, the trachea tube could be removed. In Group A, patients were extubated in a light plane of anesthesia, when they are still asleep or have swallowing reflex. In Group B, tracheal extubation was performed when the patient regained consciousness, facial grimace, spontaneous eye opening, and purposeful arm movement. After extubation, 2 L/min oxygen was administered with Venturi face mask for 10 min in both groups. Patients were transported to the ward until they breathed air with a patent airway. The extubation time, recovery characteristics and respiratory complication were recorded.

Inclusion Criteria:

• American Society of Anesthesiologists physical status aged 3-7 years

Exclusion Criteria:

• a suspected difficult airway reactive airway disease, recent upper respiratory tract infection gastrointestinal reflux obesity (body mass index>30 kg/m2