Maillard D, Ben Jebria A, Hatzfeld C
Bull Eur Physiopathol Respir. 1986 Mar-Apr;22(2):107-13.
Temporal changes in ventilation (VI) and arterial blood gases after substitution of helium (He) for nitrogen were studied in normal man during constant load exercises of 14 min duration (30 and 90 W). An abrupt switch of helium for air breathing (protocol 1; 5 subjects), or vice-versa (protocol 2; 4 subjects), was made at the 7th min. Whatever the work loads, the effect of He appeared rapidly: higher values of VI (protocol 1) were observed throughout the 7 min period of He-O2 breathing, but were only significant (p less than or equal to 0.05) during the first minute after substitution at 90 W. Reverse pattern was observed in protocol 2. Helium induced alveolar hyperventilation: sustained and significant hypocapnia (p less than or equal to 0.05) was observed during helium breathing. This effect does not seem to be a consequence of pulmonary gas exchange disturbance, in that concomitant Po2 was normal. It is suggested that He could have evoked a reflex which overrode humoral regulation. Significant increase in ventilatory CO2 responses at rest during He-O2 compared to air breathing in seven subjects (p less than or equal to 0.01) seems to confirm this hypothesis.
在正常男性进行持续14分钟（30瓦和90瓦）的恒定负荷运动期间，研究了用氦气（He）替代氮气后通气（VI）和动脉血气的时间变化。在第7分钟时，突然将氦气换成空气呼吸（方案1；5名受试者），或者反之亦然（方案2；4名受试者）。无论工作负荷如何，氦气的作用迅速显现：在整个7分钟的氦氧呼吸期间，观察到较高的VI值（方案1），但仅在90瓦替代后的第一分钟内显著（p≤0.05）。在方案2中观察到相反的模式。氦气引起肺泡过度通气：在氦气呼吸期间观察到持续且显著的低碳酸血症（p≤0.05）。这种效应似乎不是肺气体交换紊乱的结果，因为同时的Po2是正常的。有人提出，氦气可能引发了一种反射，该反射超越了体液调节。与7名受试者的空气呼吸相比，氦氧呼吸期间静息时通气CO2反应显著增加（p≤0.01），这似乎证实了这一假设。
