Katsardis C V, Desmond K J, Coates A L
Respir Physiol. 1986 Sep;65(3):257-66. doi: 10.1016/0034-5687(86)90011-3.
It has been suggested that the oxygen consumption of the respiratory muscles (VO2 resp) may play a role in limiting exercise performance in both healthy subjects and those with chronic airflow limitation (CAL). In order to measure VO2 resp reproducibly at both rest and on exercise, ventilation (VE) and total oxygen consumption (VO2) in 3 normal subjects and in 3 patients with cystic fibrosis were measured while breathing air and again when VE was stimulated by the addition of CO2 to the inspired gas. Since external work was the same it was assumed that any changes in VO2 would be due to the increase in VO2 resp during stimulated breathing allowing for the calculation of VO2 resp. The oxygen cost of breathing was higher in the patients with the increasing ventilation of exercise. These values were reproducible on repetitive measurements. It is concluded that the method employed is applicable in normal subjects and in patients with CAL, and that the O2 cost of breathing is higher in patients with CAL. The O2 cost of breathing increases as VE increases but even during exercise the VO2 resp is only a small fraction of the total VO2 and is unlikely to be a determining factor limiting exercise performance in either normal subjects or those with CAL.
有人提出，呼吸肌的耗氧量（VO2 resp）可能在限制健康受试者和慢性气流受限（CAL）患者的运动表现方面发挥作用。为了在静息和运动状态下均可重复地测量VO2 resp，对3名正常受试者和3名囊性纤维化患者在吸入空气时以及在向吸入气体中添加二氧化碳刺激通气（VE）时的通气量（VE）和总耗氧量（VO2）进行了测量。由于外部功相同，因此假设VO2的任何变化都归因于刺激呼吸期间VO2 resp的增加，从而可以计算VO2 resp。运动时通气增加，患者的呼吸氧耗更高。这些值在重复测量时具有可重复性。得出的结论是，所采用的方法适用于正常受试者和CAL患者，并且CAL患者的呼吸氧耗更高。呼吸氧耗随VE增加而增加，但即使在运动期间，VO2 resp也仅占总VO2的一小部分，不太可能是限制正常受试者或CAL患者运动表现的决定性因素。
