Modifying the ICP pulse wave: effects on parenchymal blood flow pulsatility.
Modifying the ICP pulse wave: effects on parenchymal blood flow pulsatility.
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修改 ICP 脉冲波：对实质血流脉动的影响。
DOI：
10.1152/japplphysiol.00401.2022
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Luciano,MarkG
中科院分区：
文献类型：
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作者：
Qvarlander,Sara;Dombrowski,StephenM;Biswas,Dipankar;Thyagaraj,Suraj;Loth,Francis;Yang,Jun;Luciano,MarkG
脑血流（CBF）的脉动产生颅内压（ICP）波。本研究的目的是确定外部改变 ICP 脉动是否会改变实质血流脉动。将心脏门控充气装置插入 12 只麻醉犬（犬）的外侧硬膜外腔，用于引起 ICP 脉冲的减少、反转和增强。使用激光多普勒测速仪测量每个半球的 CBF。对于 ICP 脉冲的减少和反转，观察到平均 CBF 及其幅度显着增加，并且对于反转协议观察到更大的变化。对于增强方案，还观察到同侧平均 CBF 显着增加，以及对侧 CBF 幅度降低的迹象。因此，ICP 脉冲的外部改变引起实质血流脉动的显着变化。 ICP 和 CBF 幅度之间的反比关系表明，这些变化并不是通过修改颅内 Windkessel 机制而发生的。因此，影响可能发生在低压血管，即毛细血管和/或小静脉，而不是高压动脉。然而，未来的 MRI 研究需要绘制和量化对整体脑血流的影响。新的和值得注意的这项研究表明，使用硬膜外植入犬科动物的心脏门控充气装置对 ICP 脉动进行外部修改，可以改变脑组织血流脉动。具体来说，降低收缩压会增加脑组织中的血流脉动。结果表明，CBF 搏动性的改变不太可能依赖于对供血动脉系统的 Windkessel 效应的修改，而是直接对组织和低压远端血管的影响。
Pulsation of the cerebral blood flow (CBF) produces intercranial pressure (ICP) waves. The aim of this study is to determine whether externally modifying ICP pulsatility alters parenchymal blood flow pulsatility. A cardiac-gated inflatable device was inserted in the lateral epidural space of 12 anesthetized canines (canis familiaris) and used to cause reduction, inversion, and augmentation of the ICP pulse. CBF in each hemisphere was measured using laser Doppler velocimetry. A significant increase in both mean CBF and its amplitude was observed for reduction as well as inversion of the ICP pulse, with larger changes observed for the inversion protocol. Significant increases in the mean CBF were also observed ipsilaterally for the augmentation protocol together with indications of reduced CBF amplitude contralaterally. External alteration of the ICP pulse thus caused significant changes in parenchymal blood flow pulsatility. The inverse relationship between the ICP and CBF amplitude suggests that the changes did not occur via modification of the intracranial Windkessel mechanism. Thus, the effects likely occurred in the low-pressure vessels, i.e., capillaries and/or venules, rather than the high-pressure arteries. Future MRI studies are however required to map and quantify the effects on global cerebral blood flow.NEW & NOTEWORTHYThis study demonstrated that external modification of ICP pulsatility, using a cardiac-gated inflatable device implanted epidurally in canines, alters brain tissue blood flow pulsatility. Specifically, decreasing systolic ICP increased blood flow pulsatility in brain tissue. The results suggest that the altered CBF pulsatility is unlikely to depend on modification of the Windkessel effect on the feeding arterial system but was rather an effect directly on tissue and the lower pressure distal vessels.