在逐渐的体积转移过程中,内静脉区域特异的张张和流动模式的表征
Jeremy N Cohen1, Eric T Hedge1,2, Danielle K Greaves2
1Department of Kinesiology and Health Sciences, University of Waterloo, Waterloo, Ontario, Canada.
Journal of applied physiology (Bethesda, Md. : 1985)
|May 30, 2024
概括
头向下倾斜会增加内静脉 (IJV) 的体积和流量分散,可能会增加血栓塞栓症的风险. 低压大腿袖子减少IJV体积,但对流动复杂性影响最小.
科学领域:
- 心血管生理学心血管生理学
- 流体动力学 流体动力学
- 太空医学 太空医学
背景情况:
- 内静脉 (IJV) 对于大脑外流至关重要,容易发生体积变化.
- 微重力引起的液体移动可能会导致IJV膨胀,可能导致流静止和血栓栓塞.
- 在流体转移期间区域性IJV影响和血栓栓塞风险仍未得到充分研究.
研究的目的:
- 在渐进的头向下倾斜 (HDT) 过程中描述区域性IJV体积膨胀和血流复杂性.
- 评估低压大腿手作为在HDT期间流体转移的对策.
主要方法:
- 传统的超声波和矢量流动成像被用于评估IJV体积和流动动力学.
- 使用渐进式HDT (0°, -6°, -15°, -30°) 来模拟流体移位.
- 低压大腿袖子 (40 mmHg) 在 -6° HDT期间进行了测试.
主要成果:
- 整体IJV体积与HDT显著增加,从4.6毫升 (仰卧) 增加到10.3毫升 (-30°HDT).
- 随着倾斜的增加,血液流量变得更加分散,特别是在尾部IJV区域.
- 腿袖子减少了头骨内管的体积,但没有显著改变这两个区域的流动复杂性.
结论:
- IJV表现出显著的延展性,在HDT期间容纳大体积转移.
- 在IJV中增加的流量分散,特别是在尾部区域,可能会导致血栓栓塞的风险.
- 虽然大腿袖子可以减少IJV体积,但它们对流体复杂性的影响很小,这表明它们在减轻流体静止风险方面的有效性有限.
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