在血管昏期间,大脑血管顺应的快速变化
Leena N Shoemaker1,2, Aleena Sajid1, Ronald Schondorf3
1School of Kinesiology, Western University, London, ON, Canada.
概括
在血管 (VVS) 患者中,增加脑血管顺应 (Ci) 有助于在临期间保持缩性脑血速度 (CBV). 然而,当血压明显下降时,这种补偿机制不足以保持整体的CBV.
科学领域:
- 心血管生理学心血管生理学
- 脑血管调节 脑血管调节
- 自主性功能障碍 自主性功能障碍
背景情况:
- 血管 (VVS) 的特点是血压和心率的突然下降,导致.
- 在VVS患者的头向上倾斜 (HUT) 期间维持大脑输液的补偿机制尚未完全理解.
- 了解这些机制对于开发有效的诊断和治疗策略至关重要.
研究的目的:
- 调查大脑血管顺应 (Ci) 和大脑血管抵抗 (CVR) 在支持大脑血液速度 (CBV) 在VVS患者的昏睡前期的作用.
- 测试该假设,增加的Ci和降低的CVR有助于在HUT诱导的临近昏迷期间维持CBV.
主要方法:
- 招募了15名VVS患者进行头向上倾斜 (HUT) 测试.
- 测量手指动脉血压 (ABP) 和右中脑动脉血液速度 (CBV) 波形.
- 使用修改的Windkessel模型计算个人Ci和CVR,并评估戈斯林脉动性指数 (Pi).
主要成果:
- 在临近镜期间,平均动脉血压和CVR显著下降.
- 缩CBV保持,而腹缩和平均CBV下降.
- 大脑血管合规性 (Ci) 和脉动性指数 (Pi) 均在临前显著增加,并且具有积极的相关性.
- 增加的Ci,但没有降低CVR,有助于平均CBV的变化.
结论:
- 脑血管合规性 (Ci) 在VVS患者的临近昏睡期间增加,在维持缩性CBV方面发挥作用.
- 这种补偿性Ci的增加不足以保持整体脑血速度 (CBV),而动脉血压显著下降.
- 需要进一步的研究来探索额外的补偿机制及其对VVS的临床影响.
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