Heat stroke is the most serious form of heat injury and is a medical emergency. If you suspect that someone has heat stroke — also known as sunstroke — you should call 911 immediately and render first aid until paramedics arrive.
Heat stroke can kill or cause damage to the brain and other internal organs. Although heat stroke mainly affects people over age 50, it also takes a toll on healthy young athletes.
Heat stroke often occurs as a progression from milder heat-related illnesses such as heat cramps, heat syncope (fainting), and heat exhaustion. But it can strike even if you have no previous signs of heat injury.
Heat stroke results from prolonged exposure to high temperatures — usually in combination with dehydration — which leads to failure of the body’s temperature control system. The medical definition of heat stroke is a core body temperature greater than 105 degrees Fahrenheit, with complications involving the central nervous system that occur after exposure to high temperatures. Other common symptoms include nausea, seizures, confusion, disorientation, and sometimes loss of consciousness or coma.
Symptoms of Heat Stroke
The hallmark symptom of heat stroke is a core body temperature above 105 degrees Fahrenheit. But fainting may be the first sign.
Other symptoms may include:
• Throbbing headache
• Dizziness and light-headedness
• Lack of sweating despite the heat
• Red, hot, and dry skin
• Muscle weakness or cramps
• Nausea and vomiting
• Rapid heartbeat, which may be either strong or weak
• Rapid, shallow breathing
• Behavioral changes such as confusion, disorientation, or staggering
First Aid for Heat Stroke
If you suspect that someone has a heat stroke, immediately call 911 or transport the person to a hospital. Any delay seeking medical help can be fatal.
While waiting for the paramedics to arrive, initiate first aid. Move the person to an air-conditioned environment — or at least a cool, shady area — and remove any unnecessary clothing.
If possible, take the person’s core body temperature and initiate first aid to cool it to 101 to 102 degrees Fahrenheit. If no thermometers are available, don’t hesitate to initiate first aid.
You may also try these cooling strategies:
• Fan air over the patient while wetting his or her skin with water from a sponge or garden hose.
• Apply ice packs to the patient’s armpits, groin, neck, and back. Because these areas are rich with blood vessels close to the skin, cooling them may reduce body temperature.
• Immerse the patient in a shower or tub of cool water, or an ice bath.
• If emergency response is delayed, call the hospital emergency room for additional instructions.
After you’ve recovered from heat stroke, you’ll probably be more sensitive to high temperatures during the following week. So it’s best to avoid hot weather and heavy exercise until your doctor tells you that it’s safe to resume your normal activities.