A.I. Dyachenko1, V.S. Kublanov2, E.S. Ermolaev3, A.V. Demin4, Yu.A. Shulagin5, D.S. Nevstruev6, G.S. Vylegzhanin7, A.V. Shpakov8, E.V. Khanin9, G.V. Kovrov10, R.A. Nasyrov11

1, 3–5, 8,10 Institute of Biomedical Problems of the RAS (Moscow, Russia)
2, 6, 7, 9, 11 Ural Federal University (Yekaterinburg, Russia)
1alexander-dyachenko@yandex.ru, 2kublanov@mail.ru, 31861894@mail.ru, 4a_demin2005@mail.ru, 5shulagin-yury@yandex.ru, 6nevstruev.dmitriy@mail.ru, 7grigorii.sergeevich@gmail.com, 8avshpakov@gmail.com, 9 Khanineugine@mail.ru, 10 kovrov@imbp.ru, 11roman_nasyrov00@mail.ru,9 Khanineugine@mail.ru, 10 kovrov@imbp.ru, 11roman_nasyrov00@mail.ru

It is known that sleep is a specific physiological state that is periodically replaced by wakefulness. Sensitive indicators of sleep quality are the parameters of the activity of the respiratory system: changes in respiratory movements in the chest and abdominal cavity. Violations of the parameters of the respiratory cycle (frequency, depth and volume) are often signs of serious complications. The aim of the study is investigation of changes in the parameters of respiratory movements of test volunteers under conditions of 21-day antiorthostatic hypokinesia.

Data from nighttime registrations showed that in each cycle of the study there are episodes of respiratory movements, the parameters of which are defined as apnea and hypopnea. The number of these episodes and the value of the apnea-hypopnea index increases in the second and/or third registration cycles for all volunteers. The results of a combined analysis of respiratory movement and pulse oximeter data did not reveal reliable data on the formation of sleep apnea episodes in experiments, in which there are not only interruptions in respiratory movements, but also a decrease in saturation level of less than 93%. Possible mechanisms for the formation of respiratory movements in the simulation of microgravity in terrestrial conditions are discussed.

The developed method of remote monitoring of functional changes in the parameters of respiratory movements has proven itself for use in simulated and, probably, real microgravity.

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