Yoon Youngzoon, Cho Jung H, Yoon Gilwon
Institute for Biomedical Electronics, Seoul National University of Technology, Seoul, South Korea.
J Med Syst. 2009 Aug;33(4):261-6. doi: 10.1007/s10916-008-9186-0.
Blood pressure (BP) is one of the important vital signs that need to be monitored for personal healthcare. Arterial blood pressure (BP) was estimated from pulse transit time (PTT) and PPG waveform. PTT is a time interval between an R-wave of electrocardiography (ECG) and a photoplethysmography (PPG) signal. This method does not require an aircuff and only a minimal inconvenience of attaching electrodes and LED/photo detector sensors on a subject. PTT computed between the ECG R-wave and the maximum first derivative PPG was strongly correlated with systolic blood pressure (SBP) (R = -0.712) compared with other PTT values, and the diastolic time proved to be appropriate for estimation diastolic blood pressure (DBP) (R = -0.764). The percent errors of SBP using the individual regression line (4-11%) were lower than those using the regression line obtained from all five subjects (9-14%). On the other hand, the DBP estimation did not show much difference between the individual regression (4-10%) and total regression line (6-10%). Our developed device had a total size of 7 x 13.5 cm and was operated by single 3-V battery. Biosignals can be measured for 72 h continuously without external interruptions. Through a serial network communication, an external personal computer can monitor measured waveforms in real time. Our proposed method can be used for non-constrained, thus continuous BP monitoring for the purpose of personal healthcare.
血压（BP）是个人医疗保健中需要监测的重要生命体征之一。动脉血压（BP）通过脉搏传输时间（PTT）和光电容积脉搏波（PPG）波形进行估算。PTT是心电图（ECG）的R波与光电容积脉搏波（PPG）信号之间的时间间隔。这种方法不需要气袖，仅需在受试者身上附着电极和LED/光电探测器传感器，带来的不便极小。与其他PTT值相比，在心电图R波和最大一阶导数PPG之间计算得到的PTT与收缩压（SBP）高度相关（R = -0.712），并且舒张期时间被证明适用于估算舒张压（DBP）（R = -0.764）。使用个体回归线估算SBP的百分比误差（4 - 11%）低于使用从所有五名受试者获得的回归线估算的误差（9 - 14%）。另一方面，DBP估算在个体回归线（4 - 10%）和总回归线（6 - 10%）之间没有太大差异。我们开发的设备总尺寸为7 x 13.5厘米，由单个3伏电池供电。生物信号可以连续测量72小时而不受外部干扰。通过串行网络通信，外部个人计算机可以实时监测测量的波形。我们提出的方法可用于无约束的，从而实现用于个人医疗保健目的的连续血压监测。
