Evaluation of vascular wall elasticity of human digital arteries using alternating current-signal photoplethysmography

Abstract

PurposeA simple method of estimating arterial elasticity in the human finger using a volume-oscillometric technique with photoplethysmography was principally studied under the various effects of age, sex, and cold-stress stimulation for testing the capability of using this technique in arterial elasticity analysis.MethodsAmplitude variations in the alternating current signal of the photoplethysmograph during a continuous change in transmural pressure were analyzed to obtain the blood pressure and the transmural pressure–relative volume difference relationship of the arteries. We first tested the effect of the occluding cuff size on the arterial elasticity analysis in eight subjects (ages 20–45 years) to obtain a suitable cuff size, resulting in the selection of a middle cuff with a 22 mm diameter. Blood pressure and arterial elasticity were measured in six groups of subjects separated into three age-groups of women and men (ages 20–25, 32–45, and over 50 years) for testing the effect of age and sex. Twelve subjects (ages 20–25 years) also had their blood pressure and arterial elasticity measured in three conditions under the influence of the cold-stress stimulation.ResultsAge, sex, and cold-stress stimulation had an impact on mean blood pressure (P < 0.0005, 0.025), whereas pulse pressure and heart rate were statistically unchanged by those factors. Furthermore, an advanced age (over 50 years) was found to induce an increase in relative volume difference values (P < 0.025) and upward shifting of the transmural pressure–relative volume difference relationships, whereas sex, level of mean blood pressure, and cold-stress stimulation had no influence on these forms of the index.ConclusionThis study showed the usefulness of the relative volume difference as being a mean blood pressure-independent indicator for changes in arterial elasticity.

Cuffless Blood Pressure Estimation Using Pressure Pulse Wave Signals

“…Feature extraction from the original pulse wave and the derivative of pulse wave for BP estimation has been commonly used in the literature [9,14,49]. The pulse characteristic value K was revealed to quantify vascular elasticity [50] and PIR extracted from PPG indicators can reflect the arterial diameter change [8]. Inspired by the literature, we calculated 21 features from PPW signals for BP measurement.…”

Changes in the central and peripheral circulatory system in response to the cold: own studies using impedance plethysmography and Doppler ultrasound

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The Effects of Monday Thursday Fasting on Blood Pressure and Oral Hygiene Level on Clinical Dental Profession Student

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