Mathematical modelling of non-invasive oscillometric finger mean blood pressure measurement by maximum oscillation criterion

Abstract

A mathematical study is performed to assess how the arterial pressure-volume (P-V) relationship, blood pressure pulse amplitude and shape affect the results of non-invasive oscillometric finger mean blood pressure estimation by the maximum oscillation criterion (MOC). The exponential models for a relaxed finger artery and for a partly contracted artery are studied. A new modification of the error equation is suggested. This equation and the results of simulation demonstrate that the value of pressure estimated by the MOC does not exactly agree with the value of the true mean blood pressure (the latter being defined as pressure corresponding to maximum arterial compliance). The error depends on the arterial pressure pulse amplitude, as well as on the difference between the arterial pressure pulse shape index and the arterial P-V curve shape index. In the case of contracted finger arteries, the MOC can give an overestimation of up to 19 mmHg, the pressure pulse shape index being 0.21 and the pulse amplitude 60 mmHg. In the case of relaxed arteries, the error is less evident.

An Innovative Method to Measure the Peripheral Arterial Elasticity: Spring Constant Modeling Based on the Arterial Pressure Wave with Radial Vibration

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Asymmetric time-dependent model for the dynamic finger arterial pressure–volume relationship

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Effect of external cuff pressure on arterial compliance

“…It has also been known that a lot of factors influence arterial wall compliance, such as arterial pressure, temperature and age [4][5]. Among them, pressure is one of the most sensitive factors [6][7][8], which is the difference between the internal pressure (Pi) and external pressure (Po), called transmural pressure. Internal pressure is the same as the blood pressure.…”