A.V. Demin

State Research Center RF – Institute of Biomedical Problems of RAS (Moscow, Russia)

During an interplanetary mission and on the surface of celestial bodies, astronauts will find themselves in a magnetic field with significantly lower induction than on Earth. The prolonged effect of the hypomagnetic environment on the physiological systems of a healthy person still remains poorly studied.

Aim of the work – to research for patterns in the changes of central hemodynamic parameters in model hypomagnetic conditions.

In 2020-2021, within the framework of the SIRIUS space program, ARFA-experiment was conducted at the SSC RF – IMBP RAS to study the influence of the hypomagnetic environment on the physiology of practically healthy people who were at rest. In 8 practically healthy male volunteers, heart rate, systolic and diastolic blood pressure, blood oxygenation were continuously recorded for 8 hours, and the autonomous Kerdo index (KAI) was calculated for each heart cycle. For the study, we used the portable somnological device SomnoTouch (SomnoMedics, Germany). The value of blood pressure for each heart cycle was automatically calculated using a mathematical algorithm for the speed of the pulse wave propagation from the heart to the finger of the hand based on measuring the pulse transit time (PTT), individual anthropometric data of volunteers and calibration measurements of blood pressure using an oscillometric tonometer. KAI was calculated by measuring heart rate and diastolic blood pressure. The time series of the KAI measurements were approximated by second-order polynomials that were compared and analyzed. The registration of physiological parameters in each volunteer was carried out twice: in the conditions of a natural geomagnetic field and with a model decrease in the induction of the geomagnetic field (reduce by 540 times in average). For the first time, the effect of a hypomagnetic environment with an induction of 0.090±0.039 (M±σ) µT on the cardiorespiratory system and its autonomic regulation at rest in healthy people in a sitting position was continuously investigated for 8 hours. A significant and, at the same time, multidirectional change in the parameters of central hemodynamics was revealed. The changes in heart rate and diastolic blood pressure detected in hypomagnetic conditions together led to a significant decrease in the KAI in most cases - on average by 30± 13% (M ± σ). This means that in the studied hypomagnetic environment, the parasympathic modulating effect on the activity of the cardiovascular system in most cases significantly increased. The saturation of blood hemoglobin with oxygen in hypomagnetic conditions has not changed. It is concluded that the multiplicity of the decrease in the induction of the geomagnetic field determines the way of the hemodynamic response of a healthy organism according to the sympathetic or parasympathetic type of regulation.

The obtained results can be used in the development of methods of medical control, planning of work and rest modes of astronauts in hypomagnetic conditions on the surface of Mars.

Demin A.V. Characteristics of healthy men hemodynamics in model martian hypomagnetic environment. Biomedicine Radioengineering. 2022. V. 25. № 2–3. Р. 22-30. DOI: https://doi.org/10.18127/j15604136-202202-03 (In Russian)

1. Shibanov G.P. Obitayemost kosmosa i bezopasnost prebyvaniya v nem cheloveka. M.: Mashinostroyeniye. 2007. S. 51–52. (in Russian).
2. Zhang Z., Xue Y., Yang J., Shang P., Yuan X. Biological Effects of Hypomagnetic Field: Ground-Based Data for Space Exploration. Bioelectromagnetics. 2021. V. 42(6). P. 516–531.
3. Bronshten V.A. Planeta Mars. M.: Nauka. 1977. S. 90. (in Russian).
4. Kuranova M.L., Pavlov A.E., Spivak I.M., Surma S.V., Shchegolev B.F., Kuznetsov P.A., Stefanov V.E. Vozdeystviye gipomagnitnogo polya na zhivyye sistemy. Vestnik SPbGU. Ser. 3. 2010. Vyp. 4. S. 99–107. (in Russian).
5. Artamonov A.A., Kartashova M.K., Plotnikov E.V., Konstantinova N.A. Gipomagnitnyye usloviya: sposoby modelirovaniya i otsenka vozdeystviya. Medicine of Extreme Situations. 2019. T. 21(3). S. 357–370. (in Russian).
6. Vasin A.L., Shafirkin A.V., Gurfinkel Yu.I. Vliyaniye iskusstvennogo periodicheskogo geomagnitnogo polya milligertsovogo diapazona na pokazateli variabelnosti serdechnogo ritma. Aviakosmicheskaya i ekologicheskaya meditsina. 2019. T. 53. № 6. S. 62–69. (in Russian).
7. Binhi V.N., Prato F.S. Biological effects of the hypomagnetic field: An analytical review of experiments and theories. PLoS One. 2017. Jun 27. V. 12(6).
8. Kerdo I. Ein aus Daten der Blutzirkulation kalkulierter Index zur Beurteilung der vegetativen Tonuslage. Acta neurovegetativa. 1966. Bd. 29. № 2. P. 250–268.
9. Gesche Н., Grosskurth D., Kuchler G., Patzak A. Continuous blood pressure measurement by using the pulse transit time: comparison to a cuff-based method. Eur. J. Appl. Physiol. 2012. Jan. 10. V. 112(1). P. 309–315.
10. Demin A.V., Orlov O.I., Suvorov A.V. Osobennosti gemodinamiki u zdorovykh muzhchin v gipomagnitnykh usloviyakh. Aviakosmicheskaya i ekologicheskaya meditsina. 2021. T. 55. № 2. S. 63–68. (in Russian).
11. Demin A.V., Suvorov A.V. Parasimpathetic regulation of hemodynamics in healthy men under hypomagnetic conditions. Aerospace and Environmental Medicine. 2021. V. 55. № 1/1 special issue.
12. Demin A.V., Ivanov A.I. Fizicheskaya interpretatsiya vegetativnogo indeksa Kerdo. Obrazovaniye. Nauka. Nauchnyye kadry. 2013.
    № 2. S. 151–156. (in Russian).