目的　研究失血性休克时大鼠全身氧供给 (DO2 )与氧消耗 (VO2 )关系变化。方法　按每次 4ml/kg ,每隔 0 5h分次从静脉放血 ,观察大鼠休克过程中DO2 ,VO2 ,氧摄取率 (ExtO2 )等变化。结果　失血 2 0h时平均动脉压开始明显下降 (P <0 0 1 )。在休克早期 ,DO2 呈进行性下降 ,ExtO2 出现代偿升高 ,VO2 维持相对不变 ,呈非氧供依赖关系 ;当DO2 降至2 7 64ml·min- 1 ·kg- 1 后 ,VO2 随DO2 线性降低 (P <0 0 1 ) ,即呈氧供依赖关系 ,并伴血乳酸浓度升高。结论　失血性休克时DO2 与VO2 间呈双相变化关系 ,氧供依赖关系的变化反映了全身组织缺氧的存在 Objective To study the changes of oxygen supply (DO2) and oxygen consumption (VO2) in rats during hemorrhagic shock. Methods 4ml / kg each time, every 0 5h fractional bloodletting from the venous, DO2, VO2, oxygen uptake rate (ExtO2) and other changes were observed during shock. Results The mean arterial pressure began to decrease significantly at 20 h after blood loss (P <0.01). In the early stage of shock, DO2 showed a progressive decline, ExtO2 showed compensatory increase, VO2 maintained relatively unchanged, non-oxygen dependent relationship; when DO2 dropped to 2 764ml · min-1 · kg-1, VO2 with DO2 Linearly decreased (P <0.01), that is dependent on oxygen, and accompanied by increased blood lactate concentration. Conclusions There is a biphasic relationship between DO2 and VO2 during hemorrhagic shock. The dependence of oxygen supply reflects the existence of systemic hypoxia