Shimizu M
Department of Control Engineering, Tokyo Institute of Technology, Japan.
J Biomech Eng. 1992 Feb;114(1):78-83. doi: 10.1115/1.2895453.
Blood flow in human brachial arteries, compressed by a pneumatic cuff for blood pressure measurement, is examined using several different noninvasive techniques. From the experimental results it is shown that, when arterial pressure distal to the cuff is always lower than cuff pressure, flow in the artery under the cuff becomes supercritical near the cuff downstream margin and no reflection occurs there and the reflected wave from the peripheral vascular system of the arm does not propagate beyond the cuff downstream margin. Therefore an unsteady transition from supercritical to subcritical flow occurs near the cuff downstream margin. When the peak value of distal arterial pressure exceeds cuff pressure, a reflection occurs near the cuff downstream margin. The reflection becomes stronger corresponding to decrement of the cuff pressure and the whole artery segment under the cuff inflates fully at systole. At diastole, however, the artery segment under the cuff does not collapse completely and, hence, the phenomenon becomes that of pressure wave propagation in a partially collapsed artery segment.
使用几种不同的非侵入性技术，对通过用于血压测量的气动袖带压缩的人体肱动脉中的血流进行了检查。实验结果表明，当袖带远端的动脉压始终低于袖带压力时，袖带下方动脉中的血流在靠近袖带下游边缘处变为超临界，且在该处不发生反射，来自手臂外周血管系统的反射波不会传播到袖带下游边缘之外。因此，在靠近袖带下游边缘处会发生从超临界流到亚临界流的不稳定转变。当远端动脉压的峰值超过袖带压力时，在靠近袖带下游边缘处会发生反射。反射随着袖带压力的降低而变强，并且在收缩期时袖带下方的整个动脉段会完全膨胀。然而，在舒张期，袖带下方的动脉段不会完全塌陷，因此，该现象变成了压力波在部分塌陷的动脉段中传播的现象。
