Hartmann B, Bassenge E
Institut für Angewandte Physiologie und Balneologie, Universität Freiburg.
Herz. 1989 Aug;14(4):251-9.
The servo-plethysmo-manometry, as described by Penaz, represents a method for noninvasive, continuous, true-phase measurement of the finger arterial pressure. PRINCIPLES OF MEASUREMENT The light transmission plethysmograph is integrated into a pneumatic cuff for the finger (Figure 1). The light intensity is a function of the instantaneous finger blood volume. It is assumed that the pulsatory volume fluctuations are a function of the instantaneous intra-arterial blood pressure. Since the elastic arterial walls counteract the volume fluctuations with resistance, for calibrated measurements, they must be in a fully relaxed state in the absence of transmural pressure. A criterium for assessment of the transmural pressure is the extent of the volume pulse amplitude which is relatively small in the presence of higher transmural pressure due to a lesser degree of distention of the arterial walls and which increases in association with higher extravascular pressure because of the lower transmural pressure. The registered photosignal is larger with continuous cuff pressure elevation and reduced when the intravascular pressure is exceeded. At maximal amplitude, that is, complete relaxation of the arterial wall and cessation of the transmural pressure, the servosystem is activated to regulate the cuff pressure such that the pressure in the finger cuff holds the finger blood volume constant during the pulse cycle with corresponding elevation during systole and reduction during diastole. Accordingly, the cuff pressure, with minimal delay, always can be equated with the intravascular pressure. MANOMETRY WITH THE FINAPRES Currently available Finapres models 4 and 5 are electronically similar, completely automatic and easy to handle. After positioning the finger cuff, the unit is adjusted automatically through comparison of the plethysmogram at each cuff pressure level with the predicted value stored as an algorhythm++.(ABSTRACT TRUNCATED AT 250 WORDS)
如佩纳兹所描述的伺服体积描记法测压，是一种用于无创、连续、真实相位测量手指动脉压的方法。测量原理 光电容积描记器集成在手指的气动袖带中（图1）。光强度是手指瞬时血容量的函数。假定搏动性容量波动是瞬时动脉内血压的函数。由于弹性动脉壁以阻力抵消容量波动，为进行校准测量，在无跨壁压力时它们必须处于完全松弛状态。评估跨壁压力的一个标准是容积脉搏波幅的大小，在跨壁压力较高时，由于动脉壁扩张程度较小，容积脉搏波幅相对较小，而随着血管外压力升高，由于跨壁压力降低，容积脉搏波幅会增大。随着袖带压力持续升高，记录的光信号会增大，而当血管内压力被超过时，光信号会减小。在最大波幅时，即动脉壁完全松弛且跨壁压力停止时，伺服系统被激活以调节袖带压力，使得手指袖带中的压力在脉搏周期内保持手指血容量恒定，在收缩期相应升高，在舒张期降低。因此，袖带压力总能以最小延迟等同于血管内压力。使用Finapres进行测压 目前可用的Finapres型号4和5在电子方面相似，完全自动且易于操作。放置好手指袖带后，通过将每个袖带压力水平下的容积描记图与作为算法++存储的预测值进行比较，该装置会自动进行调整。（摘要截短于250字）
