Heat Stroke
Also known as: Sunstroke, Heat Illness, Hyperthermia
Heat stroke is a life-threatening condition in which the body's core temperature rises above 104°F (40°C) and the body's cooling mechanisms fail. It is a medical emergency that can cause damage to the brain, heart, kidneys, and muscles if not treated immediately. Heat stroke can occur during intense physical activity in hot conditions or from prolonged exposure to high temperatures.
Symptoms
Causes
- Prolonged exposure to high temperatures and humidity
- Strenuous physical activity in hot conditions (exertional heat stroke)
- Failure of the body's thermoregulatory system
- Dehydration reducing the body's ability to sweat and cool
Risk Factors
- Age (young children and adults over 65)
- Strenuous outdoor exercise in heat
- Lack of acclimatization to hot weather
- Certain medications (diuretics, beta-blockers, anticholinergics)
- Obesity
- Chronic medical conditions (heart disease, diabetes)
Diagnosis
- Clinical diagnosis based on elevated core temperature and altered mental status
- Rectal temperature measurement (most accurate)
- Blood tests for organ function (liver, kidney, muscle breakdown — CK levels)
- Coagulation studies to check for disseminated intravascular coagulation
Treatment
- Immediate cooling: immersion in ice water (gold standard for exertional heat stroke)
- Evaporative cooling: cool mist with fans
- IV fluid resuscitation
- Monitoring and support of organ function in the ICU
- Benzodiazepines for shivering or seizures
Prevention
- Stay hydrated, especially during outdoor activity in heat
- Avoid strenuous activity during the hottest parts of the day
- Wear lightweight, loose-fitting, light-colored clothing
- Acclimatize gradually to hot environments
- Never leave children or pets in parked cars
When to See a Doctor
- Call 911 immediately if someone has a body temperature above 104°F with confusion
- The person is not sweating despite the heat
- Loss of consciousness or seizures occur
- Symptoms of heat exhaustion (heavy sweating, weakness, nausea) are not improving with cooling and fluids
Frequently Asked Questions
Related Conditions
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