SOME HEMODYNAMIC PARAMETERS IN UNINTENTIONAL HYPOTHERMIA

Part of Russia's territory is located in cold and temperate climate zones, where people are constantly exposed to the risk of hypothermia and cryotrauma. When exposed to cold, general metabolic processes in the body are inhibited, leading to disruption of the central nervous system, respiratory and other vital functions of the body. Studies by many authors have shown that not a single functional system remains intact during acute hypothermia.
Purpose of the study. To identify patterns of changes in central hemodynamics, cardiac activity, vascular parameters depending on the severity and period of general unintentional hypothermia.
Research methods. The study included 26 patients of both genders, aged from 18 to 50 years – 2 groups of 13 patients – with mild and moderate (group 1) and with severe (group 2) degree of unintentional hypotermia. Results. In patients with severe hypothermia, a decrease in pulse arterial pressure was recorded from admission to day 7 of observation, compared to patients with mild hypothermia. A decrease in cardiac output was also recorded on the first day of severe hypothermia. Stroke volume and ejection rate were higher in patients with severe hypothermia compared to those with mild and moderate hypothermia. In patients with mild hypothermia, an increase in pulse wave velocity was observed on days 3 and 7 of observation, compared to day 1.
Conclusion. The increase in stroke arterial pressure corresponds to adaptive changes in hemodynamics in the post-hypothermic period of general cold injury. In severe hypothermia, pulse pressure and cardiac output are lower, while stroke volume and ejection rate are higher, compared to mild hypothermia. Over time, an increase in pulse wave velocity was observed in patients with mild hypothermia.

1. https://meteoinfo.ru. Official Internet resource of the hydrometeorological center of Russia.

2. Konnov D.Yu., Konnova T.Yu., Lukyanov S.A., Shapovalov K.G. Changes in heart rhythm and breathing in acute general cold trauma. Obshhaja reanimatologija. 2015. 11(3). 16-23. DOI: https://doi.org/10.15360/1813-9779-2015-3-16-23. In Russian.

3. Kurbangaleev A.M., Popova O.V., Sorokina V.O. Threatening heart rhythm disturbances in patients with thermal trauma SPb. Medicina 2011. 21–39. In Russian.

4. Mikhailichenko M.I. etal. Pathogenetic significance of endothelial dysfunction in the formation of hyper tonicity of the peripheral vascular wall in local cold traumaPatologicheskaja fiziologija i jeksperimental'naja terapija. 2020. 64 (4). 54–61. DOI: https://doi.org/10.25557/0031-2991.2020.04.54-61. in Russian.

5. Shapovalov K.G. The Role of Endothelial Dysfunction in Tissue Alteration in Local Cold Trauma Tromboz, gemostaz i reologija. 2016. 4. 26–30. in Russian.

6. Mikhailichenko M.I., Shapovalov K.G., Figurski S.A., Mudrov V.A., Mikhailichenko S.I. Peripheral Neurodestruction in Patients with Local Cold Injury. Novosti Khirurgii. 2020. 28(5). DOI: https://dx.doi.org/10.18484/2305-0047.2020.5.536. In Russian.

7. The Montana Department of Public Health and Human Services (DPHHS). Hypothermia and Cold Related Injuries. Health and Safety Guidelines. 2015.

8. Wang H., Zhang Y. Pulse Wave Velocity as a Predictor of Cardiovascular Risk in Post-Hypothermia Patients. Frontiers in Physiology. 13. 801532. 2022 https://doi.org/10.3389/fcvm.2024.1365344.

9. Vasina, L.V., Vlasov, T.D., & Petrishchev, N.N. (2017). Functional heterogeneity of endothelium [Review]. Arterial Hypertension. 23 (2). 88–102. https://doi.org/10.18705/1607-419X-2017-23-2-88-102 in Russian.

10. Hochwald O., Jabr M., Osiovich H., et al. Preferential cephalic redistribution of left ventricular cardiac output during therapeutic hypothermia for perinatal hypoxic-ischemic encephalopathy. J. Pediatr. 2014. 164 (5) 999–1004.e1. doi: 10.1016/j.jpeds.2014.01.02.

11. Mcilvoy L. Comparison of brain temperature to core temperature: a review of the literature. Journal of Neuroscience Nursing.V. 36. 2004. 1–23.

12. Smith A.B., Jones C.D. Cardiac Output Suppression in Severe Accidental Hypothermia: A Multicenter Observational Study. Journal of Trauma and Acute Care Surgery. 90 (2). 112–120. 2021. http://dx.doi.org/10.3390/ijerph19010501.

13. Lee C., et al. Cold-Induced Endothelial Dysfunction: Role of Oxidative Stress and Vascular Inflammation. Free Radical Biology and Medicine. 135. 12–23. 2019. https://doi.org/10.3390/antiox11101958.

14. Akulova E.A., Stepanova O.V., Lovacheva O.V., et al. Changes in hemodynamics during the course of surfactant therapy in patients with hormone-dependent asthma. Tuberculosis and Lung Diseases. 2019. 97 (4). 25–29. DOI: https://doi.org/10.21292/2075-1230-2019-97-4-25-29. In Russian.