Ventilatory control during exercise in calves with artificial hearts.
Ventilatory control during exercise in calves with artificial hearts.
复制标题
人工心脏小牛运动期间的通气控制。
DOI：
10.1152/jappl.1990.68.6.2604
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Olsen,DB
中科院分区：
文献类型：
--
作者：
Huszczuk,A;Whipp,BJ;Adams,TD;Fisher,AG;Crapo,RO;Elliott,CG;Wasserman,K;Olsen,DB
为了确定心脏反射在介导运动呼吸过度中的作用，我们研究了7头装有人工心脏的小牛和7头对照小牛对跑步机运动的呼吸反应。在两组中，呼吸反应足以满足运动的代谢需求;这导致动脉PCO 2和pH值的调节，尽管植入组中没有心输出量增加。在该组中，动脉PO 2降低4 +/- 3 Torr，血乳酸升高1.1 +/- 1 mmol/l，降幅虽小但显著。当植入小牛的心输出量在实验上增加到与对照小牛中自发发生的水平相当时，通气不受影响。然而，心输出量的实验性降低导致运动呼吸过度立即增加4.56 +/- 4.3 l/min，乳酸进一步显著增加1.2 +/- 1.22 mmol/l，这与运动O2消耗量显著降低（0.32 +/- 0.13 l/min）相关。这些观察结果表明，心输出量增加的心脏或血液动力学效应都不是小腿运动呼吸过度的必然原因。
To determine the role of cardiac reflexes in mediating exercise hyperpnea, we investigated ventilatory responses to treadmill exercise in seven calves with artificial hearts and seven controls. In both groups, the ventilatory responses were adequate for the metabolic demands of the exercise; this resulted in regulation of arterial PCO2 and pH despite the absence of cardiac output increase in the implanted group. In this group, there was a small but significant reduction of arterial PO2 by 4 +/- 3 Torr and a rise of blood lactate by 1.1 +/- 1 mmol/l. When cardiac output was experimentally increased in the implanted calves to a level commensurate with that spontaneously occurring in the control calves, ventilation was not affected. However, experimental reductions of cardiac output led to an immediate augmentation of exercise hyperpnea by 4.56 +/- 4.3 l/min and a further significant lactate increase of 1.2 +/- 1.22 mmol/l that was associated with a significant decrease in the exercise O2 consumption (0.32 +/- 0.13 l/min). These observations indicate that neither cardiac nor hemodynamic effects of increased cardiac output constitute an obligatory cause of exercise hyperpnea in the calf.