Detection of special points in a photoplethysmogram

摘要

Long-term continuous registration of photoplethysmograms allows observing periodic fluctuations of regional vascular tone, which is important for non-invasive functional diagnostics of a number of diseases of the vascular system. But the relief of the photoplethysmogram within the pulse cycle in some functional states is poorly expressed, which significantly reduces the possibility of a quantitative assessment of the indicators of vascular tone. We propose a new algorithm for detecting special points of the contour of photoplethysmograms, based on the discovered relationship between the position of these special points and the duration of the pulse cycle. The efficiency of the new algorithm in cases where there is no diastolic rise has been demonstrated. It is shown that the average relative error does not exceed 5%. The proposed algorithm can be used in computer monitoring systems for vascular tone.