Sarelius I H, Sinclair J D
Am J Physiol. 1981 Feb;240(2):H177-84. doi: 10.1152/ajpheart.1981.240.2.H177.
Circulatory effects of small (approximately 10%) changes in blood volume were examined in resting and exercising dogs: controls; group A (-200 ml blood); group B (+200 ml blood); group C (+200 ml 6% dextran). In exercise, cardiac output (Q) increased more in Group A than controls (510.4 ml . kg-1 . min-1 compared to 429.6 ml . kg-1 . min-1; P less than 0.05); oxygen delivery (cardiac output x arterial O2 content) and mixed venous oxygen tension (PVO2) were unchanged from exercising controls. Hypervolemia (group B) did not change Q or O2 delivery compared to controls, but caused a greater reduction in exercise PVO2 (29.3 mmHg compared to 33.1 mmHg in controls; P less than 0.01). Resting PVO2 as raised in group C (50.0 mmHg compared to 46.3 mmHg; P less than 0.05) and exercise PVO2 was reduced less (35.5 mmHg compared to 33.1 mmHg in controls; P less than 0.05). O2 delivery in exercise was higher than in controls (123.4 ml . kg-1 . min-1 compared to 94.3 ml . kg-1 . min-1; P less than 0.001). During exercise, O2 consumption was raised from base line to 34.9 ml . kg-1 . min-1 in controls and raised further to 41.4 ml . kg-1 . min-1 in group A, 44.4 ml . kg-1 . min-1 in group B, and 41.2 ml . kg-1 . min-1 in group C (P less than 0.01). Changes of blood volume that lie within physiological limits thus significantly modify the circulatory response to changed O2 requirements, and also change the metabolic cost of exercise.
研究了静息和运动犬只血容量发生小幅度（约10%）变化时的循环效应：对照组；A组（失血200毫升）；B组（输血200毫升）；C组（输注200毫升6%右旋糖酐）。运动时，A组的心输出量（Q）增加幅度大于对照组（分别为510.4毫升·千克⁻¹·分钟⁻¹和429.6毫升·千克⁻¹·分钟⁻¹；P<0.05）；氧输送量（心输出量×动脉血氧含量）和混合静脉血氧分压（PVO₂）与运动对照组相比无变化。与对照组相比，高血容量组（B组）的心输出量或氧输送量无变化，但运动时PVO₂的降低幅度更大（分别为29.3毫米汞柱和33.1毫米汞柱；P<0.01）。C组静息时PVO₂升高（分别为50.0毫米汞柱和46.3毫米汞柱；P<0.05），运动时PVO₂降低幅度较小（分别为35.5毫米汞柱和33.1毫米汞柱；P<0.05）。运动时的氧输送量高于对照组（分别为123.4毫升·千克⁻¹·分钟⁻¹和94.3毫升·千克⁻¹·分钟⁻¹；P<0.001）。运动期间，对照组的氧消耗量从基线升至34.9毫升·千克⁻¹·分钟⁻¹，A组进一步升至41.4毫升·千克⁻¹·分钟⁻¹，B组升至44.4毫升·千克⁻¹·分钟⁻¹，C组升至41.2毫升·千克⁻¹·分钟⁻¹（P<0.01）。因此，处于生理范围内的血容量变化会显著改变对氧需求变化的循环反应，同时也会改变运动的代谢成本。
