Liu Shing-Hong, Wang Jia-Jung, Cheng Da-Chuan
Department of Computer Science and Information Engineering, Chaoyang University of Technology, Taichung, Taiwan, Republic of China.
Biomed Tech (Berl). 2009 Aug;54(4):171-7. doi: 10.1515/BMT.2009.020.
The oscillometric method has been widely used to measure arterial systolic and diastolic blood pressures, but its potential for arterial blood flow measurements still remains to be explored. The aim of this study was to non-invasively determine arterial blood flow using an oscillometric blood flow measurement system. The system consists of a pneumatic elastic cuff, an air-pumping motor, a releaser valve, a pressure transducer, and an airflow meter. To build a non-linear cuff model, we measured airflow pumped into the pneumatic cuff and cuff pressure using an airflow meter and pressure transducer during the inflation period, respectively. During the deflation period, only the pressure transducer was used to record cuff pressure. Based on the cuff model, the oscillometric blood flow waveform was obtained by integrating the oscillometric pressure waveform. We compared arterial blood flow derived from the maximum amplitude of the oscillometric blood flow waveform with Doppler-measured blood flow calculated with the diameters and blood velocities of the brachial arteries in 32 subjects who underwent diagnostic evaluations for peripheral arterial embolism. A linear correlation coefficient of r = 0.716 was found between the oscillometry- and Doppler-based blood flow measurements in the 32 subjects. These results suggest that blood flow passing through the brachial artery can be quantified non-invasively using the oscillometric approach after appropriate calibration.
示波法已被广泛用于测量动脉收缩压和舒张压，但其在测量动脉血流方面的潜力仍有待探索。本研究的目的是使用示波血流测量系统无创地测定动脉血流。该系统由一个气动弹性袖带、一个气泵电机、一个释放阀、一个压力传感器和一个气流计组成。为了建立一个非线性袖带模型，我们在充气期分别使用气流计和压力传感器测量了充入气动袖带的气流和袖带压力。在放气期，仅使用压力传感器记录袖带压力。基于袖带模型，通过对示波压力波形进行积分得到示波血流波形。我们在32名接受外周动脉栓塞诊断评估的受试者中，将示波血流波形最大振幅得出的动脉血流与用肱动脉直径和血流速度计算出的多普勒测量血流进行了比较。在这32名受试者中，示波法和多普勒法血流测量之间的线性相关系数r = 0.716。这些结果表明，经过适当校准后，使用示波法可以无创地量化通过肱动脉的血流。
