Stegemann J, Baer F M, Hoffman U
Physiologisches Institut der Deutschen Sporthochschule, Köln, Federal Republic of Germany.
Aviat Space Environ Med. 1988 May;59(5):422-7.
Our objective was to determine whether the Valsalva maneuver may be used as an indicator of fluid shift during spaceflights. The subjects, 21 healthy young men, conducted the maneuver against expiratory pressures of 20, 30, and 40 mm Hg, each lasting 30 s, at body positions of vertical, horizontal, and 6 degrees head down tilt (HDT). Heart rate was continuously recorded on a beat by beat basis together with the expiratory pressure. The increase in heart rate at equal intrathoracic pressures was maximal in the vertical position, significantly lower (p less than 0.001) in the horizontal position and lowest (p less than 0.05) in the 6 degrees HDT position. Obviously, the blood volume shift in the horizontal and 6 degrees HDT position partly compensated the impaired venous return during the Valsalva maneuver. This simple and non-invasive technique might be used to indicate the time course of blood volume shift during the initial stage of an orbital flight.
我们的目的是确定瓦尔萨尔瓦动作是否可作为太空飞行期间体液转移的一个指标。21名健康年轻男性受试者在垂直、水平以及头向下倾斜6度（HDT）的体位下，针对20、30和40毫米汞柱的呼气压力进行该动作，每次持续30秒。逐搏连续记录心率以及呼气压力。在相同胸内压下，心率增加在垂直体位时最大，在水平体位时显著降低（p<0.001），在6度HDT体位时最低（p<0.05）。显然，水平和6度HDT体位时的血容量转移部分补偿了瓦尔萨尔瓦动作期间受损的静脉回流。这种简单且无创的技术可用于指示轨道飞行初始阶段血容量转移的时间进程。
