Noninvasive Estimation of Blood Pressure Using Photoplethysmographic Signals in the Period Domain

Abstract

In order to detect hypertension at its early stage, blood pressure (BP) of an individual must be carefully monitored. Aiming to monitor BP noninvasively and continuously, this study examines a new feature, normalized harmonic area (NHA), which is extracted from photoplethysmoographic (PPG) signals in the period domain by using the discrete period transform (DPT). BP, pulse transit time (PTT), diastolic time (DT) and NHA were obtained from photoplethysmographic (PPG) signals in the period domain by using the discrete period transform (DPT). BP, pulse transit time (PTI), diastolic time (DT) and NHA were obtained from 28 subjects before and immediately after step-climbing exercise. It was found that NHA has more significant correlation wiith BP than PTT and DT in this study. The mean difference and standard deviation (Mean±SD) between the BP estimated from NHA and the reference BP obtained from a commercial oscillometric BP meter were 0.37±4.3 mmHg and 0.51±4.8 mmHg for SBP and DBP, respectively. The result indicate that NHA is potentially a useful indicator of arterial BP.

Type-2 Fuzzy System Based Blood Pressure Parameters Estimation

“…The trained IT2FSs are used to estimate SBP and DBP for remaining ten subjects and MAP are computed by equation (2 Fig. 9, Fig.…”

“…Recently, in 2005, Yan and Zhang used PPG sensor with electrocardiograph (ECG) to estimate BPPs and they stated that the normalized harmonic area of a discrete period transform of PPG signal has high correlation with BP [2].…”

Evaluation scale to assess the accuracy of cuff-less blood pressure measuring devices

“…We [34], however, found in the literature [35] that there were devices that have passed the criteria of BHS, but failed that of AAMI. [16] MD, L95% B-A plot Intra-arterial method [17] L95%, r value Intra-arterial method [18] RMSD, MD Intra-arterial method [19] MD, SD, L95% B-A plot, probability histogram Intra-arterial method and sphygmomanometer [20] MD, SD BM3 Patient Monitoring [21] MD, SD BM3 Patient Monitoring [22] MD, SD, L95% B-A plot Average of a mercury sphygmomanometer and an oscillometric device [23] MD, SD Oscillometric device [24] r value, MD, SD Finometer [25] B-A plot, tracing plot…”

“…As a result, validating approaches of the cuff-less techniques or devices vary largely from study to study in terms of the evaluation protocol, the accuracy measures, and the graphical plots they reported, as summarized in Table 1 [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. There is an urgent need to develop an evaluation standard for the cuff-less BP measuring devices that can be used by engineers and manufacturers to validate their products and by medical practitioners and lay users to select prospective devices; and therefore, this study was motivated accordingly.…”

Data-driven estimation of blood pressure using photoplethysmographic signals

“…Using wavelet analysis, Teng and Zhang (2003) suggested using two coefficients of a transform with a Mexican hat mother wavelet, together with the systolic upstroke time and the diastolic time of the pulse [18]. Others proposed normalized harmonic area and the amplitude of PPG [19], [11]. We use the systolic upstroke time and the diastolic time, gender, age, together with thousands of DWT coefficients obtained in Section II-B.…”