Heat Stroke

Heat StrokeHeat stroke is the most dangerous heat-related illness, and it can be fatal.Two characteristics define heat stroke: a core body temperature greater than 104°F (40°C) and neurological signs such as confusion, seizures, or loss of consciousness.Some of the first cells in the body to be affected are in the brain.These cells are sensitive to temperature changes.The heart also must work harder to push blood to the skin.As a person's temperature gets closer to the air temperature, the rate of heat transferred to the skin decreases.Evaporation of sweat also decreases with higher humidity.Sweating leads to further dehydration and loss of electrolytes and minerals vital for muscle and nerve cell function.As the body is no longer able to cool itself by sweating, heart rate and breathing increase to compensate.This can be aggravated by medications that alter heart function or by chronic diseases.Classic heat stroke is seen in people who are exposed to a hot environment, especially in young and elderly persons.Those with chronic diseases such as Parkinson disease, heart failure, or diabetes or who take medications can have a decreased response to dehydration.Exertional heat stroke is seen in healthy people who undergo strenuous activity in hot weather, such as marathon runners, military trainees, and football players.