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Heat Stroke

Heat Stoke Quick Overview

  • Heat stroke is a condition where the body's cooling mechanisms are overcome by heat resulting in a high core heat usually above 104 F or 40 C in adults, and 105 F or 40.5 C in children; and accompanied by mental status changes; heat stoke is a medical emergency.
  • Heat stroke is caused by a failure of the body's cooling mechanisms (sweating and/or evaporative cooling, for example) when exposed to heat.
  • Heat stroke symptoms are mainly increased body core temperature (see above) and mental status changes.
  • Heat stroke is diagnosed by the history, physical exam, and measurement of body core temperature.
  • Treatment of heat stroke is immediate cooling of the body by
    • placing the person in shade or an air conditioned room, and by covering the person with cool evaporative mists or wet sheets with fans next to the person to increase evaporative cooling;
    • placing ice packs to the groin, armpits, neck, and head have also been recommended.
  • Recovery time for heat stroke is variable; initial recovery may be done with 1-2 days in the hospital; complete recovery may take about 2 months to a year.
  • Complications of heat stroke increase the longer it takes to begin treatment; complications can include
    • internal organ damage,
    • seizures,
    • coma,
    • fetal harm or death in pregnant women, and
    • death of the person.
  • Heat stroke can be prevented by
    • drinking fluids,
    • limiting exposure to heat,
    • wearing clothing that allows evaporative cooling, and
    • recognizing the early warning signs of heat cramps and heat exhaustion and responding to those symptoms with treatment (cooling).
  • Do not leave infants, children, or pets in vehicles, and do not leave vehicles unlocked so children can get in them unattended to prevent deaths from heat stroke.

Heat Stroke Definition

Heat stroke is an emergency condition where the body's core temperature is markedly elevated (depending on who provides the definition, about 104 F [40 C] or above in adults and 105 F or 40.5 C in children) after being exposed to high environmental temperatures combined with neurologic symptoms and loss of body thermal auto regulation (ability of the brain to control the body temperature).

The elderly, pregnant females, and young children are at higher risk for heat stroke; their bodies do not cool as well as adults with no health problems). Some health-care professionals further subdivide heat strokes into exertional and non-exertional, but both have similar symptoms and treatments. Heat stroke has also been termed sunstroke and hyperthermia; heat stroke is a medical emergency.

Animals (dogs and cats, for example) can suffer heat stroke; symptoms of excessive panting and lethargy or unresponsiveness are usually diagnostic. The animal's Vet should be notified immediately; the treatments and outcomes are similar to those described below for humans.

Medically Reviewed by a Doctor on 6/19/2015

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Dehydration Pictures: Prevention Tips!

Dehydration Prevention Tip #1

Plan ahead and take extra water to all outdoor events where increased sweating, activity, and heat stress will increase fluid loss. Encourage athletes and people who work outside to replace fluids at a rate that equals the loss.

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