The recent heat waves experienced in the Cape have given rise to an increase in heat related incidents. These conditions occur when excess environmental heat overwhelms the body's thermoregulatory mechanisms. Thermoregulation is the means by which the body is able to maintain an optimal functioning temperature, despite the ambient temperature of the surrounds and is achieved by mechanisms such as sweating and the dilation of peripheral blood vessels.
The generation and maintenance of body heat may be dictated through metabolism, muscle activity, and the environmental temperature. In order to maintain a functioning temperature, when body heat rises, peripheral blood vessels dilate and cardiac output increases resulting in a shunting of blood flow closer to the surface where it can be cooled. Additionally, sweating aids cooling by providing water on the skins surface, which evaporates and in turn further cools the body. When there is a high environmental temperature and high humidity value, heat dissipation through evaporation may be hindered.
- Generalized skin conditions (sunburn)
- Mental illness
- Cardiopulmonary disease
- Age >65 years
- Stimulant abuse including: cocaine, amphetamines, MDMA (ecstasy)
Exertional heat stroke occurs when the body temperature rises in a healthy person who exercises strenuously in a hot environment.
Deep and painful spasms within the most actively used muscles and are a direct result of salt depletion. Affect muscles become harden and tender to touch, with spams which can be debilitating.
- Curriero FC, Heiner KS, Samet JM, et al. Temperature and mortality in 11 cities of the eastern United States. American Journal of Epidemiology 2002;155(1):80-87