基于光电容积脉搏波描记法(Photo Plethysmo Graphy,PPG)的柔性传感器可进行心率(Heart Rate,HR)和血压(Blood Pressure,BP)检测,但是对其检测结果的标定报道甚少.据此,本文提出一种基于模拟血液循环的反射式PPG心率检测和血压标定系统.以蠕动泵来产生脉动流,通过调节其转速的大小来控制模拟血液输送的频率和压力,从而引起弹性乳胶管内模拟血液体积的变化,而改变反射光的信号周期与强度,贴近于人体脉搏测量过程的实际场景.该系统心率检测误差均值为0.277 78,95％一致性界限为(-2.595 62,3.151 17),所测收缩压(Systolic Blood Pres-sure,SBP)和舒张压(Diastolic Blood Pressure,DBP)的拟合优度分别为0.971 85和0.981 11.经标定后的柔性PPG传感器对4名志愿者检测的SBP和DBP的平均偏差(Mean Deviation,MD)±标准差(Standard Deviation,SD)均值分别为(1.21±2.16)mmHg和(0.76±2.02)mmHg,均符合且远小于美国医疗仪器促进协会(Association for the Advancement of Medical Instrumentation,AAMI)所制定的衡量血压计精度的标准指标(5±8)mmHg.结果表明,该系统能够准确高效地标定柔性PPG传感器,为实现便携式可穿戴设备的精准血压检测提供标定基础.
Research on Calibration Method of Flexible Blood Pressure Sensor Based on Photoplethysmography
The flexible sensor based on photo plethysmo graphy(PPG)can detect heart rate(HR)and blood pressure(BP),but the calibration of their detection results is rarely reported.Therefore,this paper proposes a reflective PPG heart rate detection and blood pressure calibration system based on simulated blood circulation.The peristaltic pump is used to generate pulsating flow,and the frequency and pressure of simulated blood delivery are controlled by adjusting its rotational speed,thus causing the change of the volume of simulated blood in the elastic latex tube and changing the signal period and intensity of reflected light,which is closer to match the actual scenario of human pulse measurement process.The mean val-ue of heart rate detection error of the system is 0.277 78,and the 95％consistency limit is(-2.595 62,3.151 17).The good-ness of fit of measured systolic blood pressure(SBP)and diastolic blood pressure(DBP)are 0.971 85 and 0.981 11,respec-tively.The mean value of mean deviation(MD)±standard deviation(SD)of SBP and DBP detected by the calibrated flexi-ble PPG sensor on four volunteers is(1.21±2.16)mmHg and(0.76±2.02)mmHg,respectively,which are in line with and far less than the standard index of 5±8 mmHg for measuring the accuracy of blood pressure monitors set by the associa-tion for the advancement of medical instrumentation(AAMI).The results show that this system can calibrate the flexible PPG sensor accurately and efficiently,which provides the calibration basis for the accurate blood pressure detection of por-table wearable devices.
万方数据
维普
