Group 1 received placebo(NaCl 0.9%) 1 ml/kg immediately before CPR,and immediately after restoration of spontaneous circulation(ROSC).

• 1组；在心肺复苏(CPR)前和自主循环恢复(ROSC)后分别立即给两个剂量的0.；9%25生理盐水1ml/kg;