伺服零微血管测压系统的研究

Study on a Sero-null Microvascular Pressure Measuring System

本文介绍了一个改进的微循环测压系统。它是根据Wiederhielm提出的阻抗平衡压力检测原理而设计的。该系统包括微压检测、信号处理及有关的外设。系统频响优于 20Hz,其非线性误差在0—80mmHg范围内优于1％。应用该系统已成功地检测了蟾蜍肠系膜各管径级(最小达14μ)微血管内的血压参数。实践表明,本系统为微循环研究提供了可靠而实用的测压手段,可直接用于单根微血管内压力和脉搏波的记录、测量跟踪和各参数的定量分析。

On the basis of the servo-controlled pressure recording system described by Wiederhielm (1964), the authors have developed a servo-null micropressure measuring system incorporating a microcomputer. This system had successfully accomplished micropipette's impaling, picking up micropressure singnal, synchronous detection, data recording and processing.In the servo-controlled pressure recording the micropipette is filled with a low-resistance 2M NaCl (compared to plasma) and, after inserting into a vessel, motion of the interface between electrolyte solution and plasma due to changes in intravascular pressure produced changes in electrical resistance. And then, it goes through a suit of servo-mechanism trying to return the bridge balance. A pressure could be detected, at the same time, that really indicated the blood pressure of this vessel.This micropressure detecting apparatus is consisted of three sections: minimal pressure servo probe, signal detector and. null-servo main device.