Heatstroke, the most severe heat-related illness, is clinically defined as body core temperature (Tcore) higher than 40.6?°C 6. During heat waves, heatstroke occurred in an epidemic form, as witnessed by sharply increased admissions in both hospital emergency department (ED) visits and intensive care unit (ICU) 16. Heatstroke is associated with high mortality rate, and also contributes to late deaths resulting from exacerbation of many pre-existing health conditions 30.
Heatstroke can rapidly become life threatening and people with severe heatstroke symptoms have little time to seek treatment in ED or hospitals 31. It has been observed that most excess deaths were at home during heat waves 38,43, for example, during the 2003 European heat wave more than 50% of the fatalities in France occurred in homes 21. However, so far studies of heat-related mortality have mainly focused on the increase in ambient temperature. The effect of indoor environmental parameters on heatstroke has never been investigated and thus warrants immediate attention.
Early recognition is an effective approach to prevent the risk of heatstroke. However, the time course of the development of heatstroke is unknown, because there is a lack of the clinical data. Our objective is to predict the time course of the development of heatstroke based on thermoregulation mechanism. Biologically speaking, heatstroke occurs when the metabolic and environmental accumulated heat exceeds the body’s ability to dissipate that leads to an excessive increase in Tcore 13.
The objective of our work is to predict and hence early recognize heatstroke at home using human thermoregulatory model. We first extend the classical human thermoregulatory model so as to consider the role of high temperature in the development of heat-related illness and then analyze the effects of indoor environmental parameters on the time course of heatstroke development.