Extreme Heat (Hyperthermia)

Hyperthermia is elevated body temperature due to failed thermoregulation that occurs when a body produces or absorbs more heat than it dissipates. Extreme temperature elevation then becomes a medical emergency requiring immediate treatment to prevent disability or death. Heavy sweating, rapid breathing and a fast, weak pulse. If the condition progresses to heat stroke, then hot, dry, skin is typical as blood vessels dilate in an attempt to increase heat loss. An inability to cool the body through perspiration may cause the skin to feel dry. Diagnosis: The presence of signs and symptoms related to hyperthermia syndromes, such as extrapyramidal symptoms characteristic of neuroleptic malignant syndrome, and the absence of signs and symptoms more commonly related to infection-related fevers, are also considered in making the diagnosis.

If fever-reducing drugs lower the body temperature, even if the temperature does not return entirely to normal, then hyperthermia is excluded. Treament: Drinking water and turning a fan or dehumidifying air conditioning unit on the affected person may improve the effectiveness of the body's evaporative cooling mechanisms. When the body temperature reaches about 40 ?C, or if the affected person is unconscious or showing signs of confusion, hyperthermia is considered a medical emergency that requires treatment in a proper medical facility.

In a hospital, more aggressive cooling measures are available, including intravenous hydration, gastric lavage with iced saline, and even hemodialysis to cool the blood. Epidemology: Between 1992 and 2006 in the United States, 68 crop workers died from heat stroke, representing a rate 20 times that of US civilian workers overall. An extreme 2003 European heat wave caused tens of thousands of deaths.