Postextubation airway obstructions requiring nasal airway placement were less frequent in group SR ( 14 cases versus 2 cases in group S , p < 0.05 ) ; patients in group SR also had a shorter mean time to awakening ( 19.5 minutes versus 15.8 minutes , p < 0.05 ) and a shorter mean time to orientation ( 31.4 minutes versus 26.1 minutes , p < 0.05 ) .