Wang D S, Sun L, Xiang Q L, Ren W
Institute of Space Medico-Engineering, Beijing, China.
Space Med Med Eng (Beijing). 1999 Dec;12(6):459-63.
One of the most profound circulatory changes that occur in man during exposure to microgravity is a cephalad redistribution of fluid. Central venous pressure (CVP) is not only an important standard for determining the cephalad redistribution of fluid but also the unique valuable means for measuring continuously cardiac filling pressure under simulated weightlessness (SW) and microgravity, and has a relationship with neurohumoral [correction of nerohumoral] regulation. With the development of manned spaceflight, the researches in space suggested that CVP did not increase, which is directly contradictory to the previous results under SW. This paper mainly discusses the changes of CVP and the effects of countermeasures on CVP under SW and microgravity, and the mechanisms of decreased CVP under microgravity. It is postulated that more suitable SW models, more studies about the area of low pressure including especially pulmonary circulation, and comprehensive studies in multiple systems are needed.
人类在暴露于微重力环境期间发生的最深刻的循环变化之一是体液向头部分布。中心静脉压(CVP)不仅是确定体液向头部分布的重要指标,也是在模拟失重(SW)和微重力条件下连续测量心脏充盈压的唯一有价值的手段,并且与神经体液调节有关。随着载人航天的发展,太空研究表明中心静脉压并未升高,这与之前在模拟失重条件下的结果直接矛盾。本文主要讨论了模拟失重和微重力条件下中心静脉压的变化、应对措施对中心静脉压的影响以及微重力条件下中心静脉压降低的机制。推测需要更合适的模拟失重模型、更多关于低压区域(尤其是肺循环)的研究以及多系统的综合研究。