While the pressure of PEEP increased from 0 to 30 cmH 2O, TXB 2 increased by 41 0%, 6 Keto PGF 12 increased by 21 1% and the ratio of TXA 2/PGI 2 decreased.

• PEEP压力从0增至30cmH2O，TXB2增加41.；0%25，6－keto－PGF12增加21