Laboratory Analysis of the Renal Function Changes Under Long-Term Exposure to Extremely Low Ambient Temperatures: Case Report.

The study subject was a healthy, 47-year-old man, a low temperature Guinness World Record holder. He spent 50 days alone in Rovaniemi, Lapland, and functioned in the ambient temperature ranging from +2°C to -37°C. He did not use sources of heat, he did not eat warm meals or drink hot water, and did not dry his clothes. He slept in an igloo, on an ice cover of 20-30 cm. He spent 10 hours a day in a sleeping bag and for the remaining time he walked, skied, or rode a bicycle, and practiced swimming. The aim of the study was a laboratory assessment of renal capacity in a man exposed to long-term extremely low ambient temperatures. The study was approved by the Ethical Committee at the Regional Medical Chamber in Krakow, Poland (approval No.: 194/KBL/OIL/2019). Twice during the observation, urine and blood were collected and analyzed: before and after the prolonged exposure to extremely low ambient temperatures. Changes were seen in many blood and urine parameters, but in urine, they were more significant. In urine, decreased values of sodium (by 53.9%), potassium (by 22.6%), creatinine (by 65.5%), urea (by 61.3%), uric acid (by 58.4%), and protein (by 50%) were observed. Neutrophil gelatinase-associated lipocalin (NGAL) increased by 34%. Absence of calcium oxalate excretion was reported relative to the value before the exposure to cold. In blood, increased values of interleukin-6 (by 60%) and ß-2-microglobulin (by 26.9%) were observed. Erythropoietin decreased by 22.4%. No changes were noted in estimated glomerular filtration rate. The study subject lost 10 kg in weight. On the basis of the results obtained during the observation, it can be determined that the probable cause of changes in the laboratory results of the subject was the diet used, and not a dysfunction of the excretory system. The body weight loss and activation of compensating mechanisms focused on saving vitally important diet components, caused by the insufficient diet, exclude the theory of a negative effect of exposure to extremely low temperatures on renal filtration function.

The Effect of Extreme Cold on Complete Blood Count and Biochemical Indicators: A Case Study.

Regular exposure to a cold factor-cold water swimming or ice swimming and cold air-results in an increased tolerance to cold due to numerous adaptive mechanisms in humans. Due to the lack of scientific reports on the effects of extremely low outdoor temperatures on the functioning of the human circulatory system, the aim of this study was to evaluate complete blood count and biochemical blood indices in multiple Guinness world record holder Valerjan Romanovski, who was exposed to extremely cold environment from -5 °C to -37 °C for 50 days in Rovaniemi (a city in northern Finland). Valerjan Romanovski proved that humans can function in extremely cold temperatures. Blood from the subject was collected before and after the expedition. The subject was found to have abnormalities for the following blood indices: testosterone increases by 60.14%, RBC decreases by 4.01%, HGB decreases by 3.47%, WBC decreases by 21.53%, neutrocytes decrease by 17.31%, PDW increases by 5.31%, AspAT increases by 52.81%, AlAT increase by 68.75%, CK increases by 8.61%, total cholesterol decreases by 5.88%, HDL increases by 28.18%. Percentage changes in other complete blood count and biochemical indices were within standard limits. Long-term exposure of the subject (50 days) to extreme cold stress had no noticeable negative effect on daily functioning.