A.Yu. Tyurin-Kuz’min1, P.E. Soldatov2

1, 2 Institute of Biomedical Problems of the Russian Academy of Sciences (Moscow, Russia)
1 alturkuz@mail.ru, 2 soldatov@imbp.ru

When studying the influence of external influences on a living organism, it is important that the research methods themselves have as minimal an impact as possible. For this purpose, it is desirable to work with intact (non-anesthetized) animals using non-invasive techniques. Such techniques include, for example, photoplethysmography, which allows obtaining a pulsogram containing information on the activity of the cardiovascular system. Anesthesia of animals is unacceptable, for example, when studying the effects of altered respiratory environments, since respiratory gases (under certain conditions) themselves can have narcotic activity. In addition, the clarity of the form of presentation of the results is important, simplifying the connection of the observed parameters with the state of the animal's body.

To develop a method for visually assessing the rhythmic components of cardiovascular system regulation based on the parameters of the pulsogram. Based on the division of the pulseogram into sections of decreasing and increasing duration of interpulse intervals, the axis was used to observe patterns of changes in the rhythmic components of regulation of the cardiovascular system of laboratory rats under the influence of hypoxia with an increased content of CO2 (simulation of respiratory failure) and subsequent recovery by hyperoxia without and with the replacement of nitrogen with inert gases (helium and argon). The method can be used as an additional one to studies in which it is possible to obtain rhythmograms. In addition, the clarity of the dynamics of processes on the obtained scatterograms and the use in this article of only a small part of the information displayed on them suggests the possibility of further development of the method.

Tyurin-Kuz’min A.Yu., Soldatov P.E. A method for processing pulsegrams for the purpose of visually assessing the state of the cardiovascular system of laboratory animals during breathing in a modified gas environment. Biomedicine Radioengineering. 2025. V. 28. № 6. P. 73–82. DOI: https://doi.org/10.18127/ j15604136-202506-08 (In Russian)

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