Vascular Diseases Center, University of Ferrara, Ferrara, Italy.
J Appl Physiol (1985). 2012 Mar;112(5):904-10. doi: 10.1152/japplphysiol.00712.2011. Epub 2011 Dec 15.
We assessed the hemodynamic effects induced by the thoracic pump in the intra- and extracranial veins of the cerebral venous system on healthy volunteers. Activation of the thoracic pump was standardized among subjects by setting the deep inspiration at 70% of individual vital capacity. Peak velocity (PV), time average velocity (TAV), vein area (VA), and flow quantification (Q) were assessed by means of echo color Doppler in supine posture. Deep respiration significantly increases PV, TAV, and Q, but it is limited to the extracranial veins. To the contrary, no significant hemodynamic changes were recorded at the level of the intracranial venous network. Moreover, at rest TAV in the jugular veins was significantly correlated with Q of the intracranial veins. We conclude that the modulation of the atmospheric pressure operated by the thoracic pump significantly modifies the hemodynamics of the jugular veins and of the reservoir of the neck and facial veins, with no effect on the vein network of the intracranial compartment.
我们评估了胸泵在健康志愿者脑静脉系统的颅内和颅外静脉中引起的血流动力学效应。通过将深吸气设置为个体肺活量的 70%，在受试者之间标准化了胸泵的激活。通过仰卧位的回声彩色多普勒评估峰值速度 (PV)、时间平均速度 (TAV)、静脉面积 (VA) 和流量定量 (Q)。深呼吸显著增加 PV、TAV 和 Q，但仅限于颅外静脉。相反，在颅内静脉网络水平没有记录到明显的血流动力学变化。此外，在休息时，颈静脉中的 TAV 与颅内静脉的 Q 显著相关。我们得出结论，由胸泵调节的大气压显著改变了颈静脉和颈面部静脉储器的血流动力学，对颅内腔室的静脉网络没有影响。
