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在中枢低热血症和体积负荷期间的补偿储备指数在健康的年轻人和老年人中:试点研究的试点研究
Josh Foster1,2, Daniel Gagnon1,3, Caitlin P Jarrard1
1Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
Physiological reports
|August 6, 2024
概括
年长的成年人在下体负压挑战期间显示减弱的补偿储备指数 (CRI) 减少. 年龄在体积加载期间没有影响CRI,这表明特定于年龄的对心血管压力的反应.
科学领域:
- 心血管生理学心血管生理学
- 生物医学工程 生物医学工程
- 老年学是指老年学的学科.
背景情况:
- 补偿储备指数 (CRI) 是一种非侵入式的方法,它通过对光聚缩学信号的机器学习来评估心血管稳定性.
- 在年轻人中CRI算法的发展需要对其在老年人群中的有效性进行研究.
- 了解CRI与年龄相关的调节对于其在不同年龄组的临床应用至关重要.
研究的目的:
- 为了比较年轻和年长的健康成年人对心血管挑战 (下体负压和体积负载) 的CRI反应.
- 为了确定年龄是否会影响正常热和高热压力期间的补偿储备指数.
- 为了研究体积负载对不同年龄组的CRI的影响.
主要方法:
- 招募了11名年轻 (20-36岁) 和10名年长 (61-75岁) 的健康参与者.
- 施用了等级的正常热和高热下体负压 (LBNP),高达30mmHg.
- 进行液输注 (15毫升/公斤) 进行体积加重,同时保持高热.
主要成果:
- 与年轻人相比,老年人在正常热和高热LBNP期间表现出更高的CRI30 mmHg.
- 在其他LBNP阶段的年龄组之间没有观察到CRI的显著差异.
- 在任何年龄组中,体积负荷都没有改变CRI,无论高温症如何.
结论:
- 年龄减弱了CRI在最大下体负压期间的下降,但仅在30 mmHg时.
- 在所有参与者,不论年龄,在体积加载期间,补偿性储备指数保持不变.
- 需要进一步的研究,以确定观察到的CRI年龄差异是否反映了下体负压耐受度的变化.
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