scholarly journals Estimation of Blood Pressure in the Radial Artery Using Strain-Based Pulse Wave and Photoplethysmography Sensors

Micromachines ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 556 ◽  
Author(s):  
Yu-Jen Wang ◽  
Chia-Hsien Chen ◽  
Chung-Yang Sue ◽  
Wen-Hsien Lu ◽  
Yee-Hsuan Chiou
Keyword(s):  
Blood Pressure ◽  
Radial Artery ◽  
Strain Gauge ◽  
Pulse Wave ◽  
Estimation Method ◽  
Force Sensor ◽  
Pressing Force ◽  
The Relationship ◽  
Vascular Status

Blood pressure (BP) is a crucial indicator of cardiac health and vascular status. This study explores the relationship between radial artery BP and wrist skin strain. A BP estimation method based on the physical model of wrist skin tissues and pulse wave velocity (PWV) is proposed. A photoplethysmography (PPG) sensor and strain gauge are used in this method. The developed strain-based pulse wave sensor consists of a pressing force sensor, which ensures consistent pressing force, and a strain gauge, which measures the cardiac pulsation on the wrist skin. These features enable long-term BP monitoring without incurring the limb compression caused by a cuff. Thus, this method is useful for individuals requiring continuous BP monitoring. In this study, the BP of each participant was measured in three modes (before, during, and after exercise), and the data were compared using a clinically validated sphygmomanometer. The percentage errors of diastolic and systolic BP readings were, respectively, 4.74% and 4.49% before exercise, 6.38% and 6.10% during exercise, and 5.98% and 4.81% after a rest. The errors were compared with a clinically validated sphygmomanometer.

Age dependence of brachial cuff-based ambulatory PWV in end-stage kidney disease patients undergoing long-term peritoneal dialysis

2021 ◽  
pp. 089686082199692
Author(s):  
Vasilios Vaios ◽  
Panagiotis I Georgianos ◽  
Georgia Vareta ◽  
Dimitrios Divanis ◽  
Evangelia Dounousi ◽  
...  
Keyword(s):  
Risk Factors ◽  
Blood Pressure ◽  
Heart Rate ◽  
Peritoneal Dialysis ◽  
Kidney Disease ◽  
Pulse Wave ◽  
Age Dependence ◽  
End Stage Kidney Disease ◽  
End Stage

Background: The newly introduced device Mobil-O-Graph (IEM, Stolberg, Germany) combines brachial cuff oscillometry and pulse wave analysis, enabling the determination of pulse wave velocity (PWV) via complex mathematic algorithms during 24-h ambulatory blood pressure monitoring (ABPM). However, the determinants of oscillometric PWV in the end-stage kidney disease (ESKD) population remain poorly understood. Methods: In this study, 81 ESKD patients undergoing long-term peritoneal dialysis underwent 24-h ABPM with the Mobil-O-Graph device. The association of 24-h oscillometric PWV with several demographic, clinical and haemodynamic parameters was explored using linear regression analysis. Results: In univariate analysis, among 21 risk factors, 24-h PWV exhibited a positive relationship with age, body mass index, overhydration assessed via bioimpedance spectroscopy, diabetic status, history of dyslipidaemia and coronary heart disease, and it had a negative relationship with female sex and 24-h heart rate. In stepwise multivariate analysis, age ( β: 0.883), 24-h systolic blood pressure (BP) ( β: 0.217) and 24-h heart rate ( β: −0.083) were the only three factors that remained as independent determinants of 24-h PWV (adjusted R 2 = 0.929). These associations were not modified when all 21 risk factors were analysed conjointly or when the model included only variables shown to be significant in univariate comparisons. Conclusion: The present study shows that age together with simultaneously assessed oscillometric BP and heart rate are the major determinants of Mobil-O-Graph-derived PWV, explaining >90% of the total variation of this marker. This age dependence of oscillometric PWV limits the validity of this marker to detect the premature vascular ageing, a unique characteristic of vascular remodelling in ESKD.

scholarly journals Photoplethysmography-Based Continuous Systolic Blood Pressure Estimation Method for Low Processing Power Wearable Devices

2019 ◽  
Vol 9 (11) ◽  
pp. 2236 ◽  
Author(s):  
Rolandas Gircys ◽  
Agnius Liutkevicius ◽  
Egidijus Kazanavicius ◽  
Vita Lesauskaite ◽  
Gyte Damuleviciene ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
High Performance ◽  
Pulse Wave ◽  
Blood Pressure Measurement ◽  
Sampling Rate ◽  
Estimation Method ◽  
Wearable Devices ◽  
Wave Steepness ◽  
Processing Power

Regardless of age, it is always important to detect deviations in long-term blood pressure from normal levels. Continuous monitoring of blood pressure throughout the day is even more important for elderly people with cardiovascular diseases or a high risk of stroke. The traditional cuff-based method for blood pressure measurements is not suitable for continuous real-time applications and is very uncomfortable. To address this problem, continuous blood pressure measurement methods based on photoplethysmogram (PPG) have been developed. However, these methods use specialized high-performance hardware and sensors, which are not available for common users. This paper proposes the continuous systolic blood pressure (SBP) estimation method based on PPG pulse wave steepness for low processing power wearable devices and evaluates its suitability using the commercially available CMS50FW Pulse Oximeter. The SBP estimation is done based on the PPG pulse wave steepness (rising edge angle) because it is highly correlated with systolic blood pressure. The SBP estimation based on this single feature allows us to significantly reduce the amount of data processed and avoid errors, due to PPG pulse wave amplitude changes resulting from physiological or external factors. The experimental evaluation shows that the proposed SBP estimation method allows the use of off-the-shelf wearable PPG measurement devices with a low sampling rate (up to 60 Hz) and low resolution (up to 8-bit) for precise SBP measurements (mean difference MD = −0.043 and standard deviation SD = 6.79). In contrast, the known methods for continuous SBP estimation are based on equipment with a much higher sampling rate and better resolution characteristics.

Abstract 49: Blood Pressure is Correlated with Arterial Stiffness in Previous Preterm Preeclamptics

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Sarah A Hale ◽  
Carole McBride ◽  
Ira M Bernstein
Keyword(s):  
Blood Pressure ◽  
Arterial Stiffness ◽  
Pulse Wave ◽  
Follicular Phase ◽  
Time Interval ◽  
Nulliparous Women ◽  
History Of ◽  
Artery Flow ◽  
Flow Waveforms ◽  
The Relationship

Blood pressure (BP) and arterial stiffness are known to be correlated and have independent value in assessing risk for future cardiovascular disease. The objective of the current study was to evaluate the relationship between arterial stiffness, as measured by pulse wave velocity (PWV), and BP, in nulliparous women (CTL) as compared to women with a history of preterm preeclampsia (PE). Twenty-eight nulliparous women and 19 PEs were evaluated during the follicular phase of the menstrual cycle. There were no differences in age: CTL: 30.9 ± 0.9 vs. PE: 31.3 ± 1.1 yrs, p = 0.78. BMI was significantly lower in CTL: 24.4 ± 1.1 vs. PE: 28.5 ± 1.6 kg/m 2 , p = 0.02. Time interval from delivery to evaluation in PE was 2.46 ± 0.29 yrs. PWV was measured using simultaneous electrocardiographic tracings and ultrasound determined arterial flow waveforms and calculated as the estimated distance divided by the time interval between EKG r-wave peak and ultrasound derived peak popliteal artery flow. Beat to beat BPs were measured in the seated position using the Finapres Pro and averaged over one minute. The data are expressed as mean ± SE. P < 0.05 accepted for significance. MAP was significantly lower in CTLs than in PEs: 87.7 ± 1.4 vs PE: 94.4 ± 2.4, p = 0.02. There was no difference in PWV between CTL and PE: CTL: 2.51 ± 0.05, PE: 2.52 ± 0.06, p = 0.88. Pulse pressure was significantly correlated with PWV in PEs, but not in CTLs, CTL: r = 0.26, p = 0.18, PE: r = 0.54, p = 0.02. Systolic BP was significantly correlated in both CTL and PE with PWV: CTL: r = 0.43, p = 0.02, PE: r = 0.53, p = 0.02. There was a trend for a significant positive correlation between diastolic BP and PWV in the PE group, but not in the CTL: r = 0.11, p = 0.57, PE: r = 0.44, p = 0.06. The same trend existed in the PE for MAP and PWV: CTL: r = 0.27, p = 0.17, PE: 0.44, p = 0.06. For women who have had previous PE, a significant relationship exists between BP and arterial stiffness, while women who have not had a pregnancy do not exhibit this relationship. Pregnancy likely unmasks subclinical cardiovascular derangement resulting in PE, and persisting years beyond delivery. Our observations suggest that for women who have had prior PE evaluating the relationship between arterial stiffness and BP may be more informative for cardiovascular risk than assessing PWV alone.

Sign in / Sign up

Export Citation Format

Share Document