The arterial and right atrium blood were taken for blood gas analysis at the following time: TLV 15 min( t 1), OLV 30 min ( t 2), OLV 60 min( t 3), TLV 30 min( t 4), and the Qs/Qt was calculated.

• 在麻醉后双肺通气 (two -lungventilation ,TLV) 15min(t1) ,OLV 30min(t2 ) ,OLV 6 0min(t3) ,TLV 30min(t4 )时间点抽取动脉血和右心房血 ,行血气分析检查 ,并计算肺内分流量 (Qs/Qt)。