低血容量性休克大鼠全身氧动力学的变化研究

目的：研究低血容量性休克时全身氧动力学的变化特点。方法：按４ｍｌ／ｋｇ，每隔０．５分次从静脉放血，观察大鼠休克过程中全身氧供给（ＤＯ２），氧消耗（ＶＯ２）和氧摄取率（ＥｘｔＯ２）的变化。结果：失血后１．５小时血红蛋白浓度开始显著降低，心率明显加快，失血２．０小时平均动脉压明显下降，此时ＤＯ２亦开始进行性下降，由于ＥｘｔＯ２出现代偿升高，ＶＯ２维持相对不变；

Characteristics of oxygen kinetics in rats during hemorrhagic shock

Objective:To investigate the characteristics of oxygen kinetics during hemorrhagic shock.Methods:A rat model of hemorrhage was established by withdrawing venous blood in 4 ml/kg every 0 5 hour interval.Systemic oxygen delivery (O 2),oxygen consumption (O 2) and oxygen extraction (ExtO 2) were measured in rats during hemorrhagic shock.Results:Blood hemoglobin concentrations decreased (all P <0 05) and heart rates significantly increased (all P <0 05) at 1 5 hours of hemorrhage.2 hours after hemorrhage,mean arterial pressure significantly lowered (all P <0 01),while O 2 progressively decreased,O 2 remained relative stable which was attributed to an increase in ExtO 2 compensatively.After 3 0 hours of hemorrhage,O 2 significantly decreased ( P <0 01) associated with reduction in O 2,manifesting dependence of O 2 on O 2,and it was associated with elevation of blood lactate concentrations.Conclusions:Dependency of O 2 on O 2 exists in hemorrhagic shock,and such relation is indicative of body tissue hypoxia.