min,and SpO2,PETCO2,ICP and blood gas parameters of radial artery and internal jugular vein were monitored. Cerebral arteriovenous difference of oxygen(Da-vO2=CaO2-CjO2)and cerebral extraction of oxygen(CEO2=SaO2-SjvO2)were calculated and analyzed.

• 监测脉搏氧饱和度(SpO2)、潮气末二氧化碳分压(PETCO2)、颅内压(ICP)和桡动脉、颈内静脉血气 ,计算脑动静脉氧含量差(Da - jvO2=CaO2-Cj vO2)和脑氧摄(CEO2=SaO2-SjvO2)。