First Aid and Emergencies
Heat
Exhaustion and Heat Stroke
Heat exhaustion
occurs when your body cannot sweat enough to cool you off. It generally develops
when you are working or exercising in hot weather. Symptoms include:
Fatigue, weakness, headache, dizziness, or nausea.
Skin that is cool, moist, pale, or flushed.
Heat exhaustion can sometimes
lead to heat stroke , which requires emergency
treatment. Heat stroke happens when you stop sweating and your body temperature
continues to rise, often to 40.5°C (105°F)
or higher. Symptoms of heat stroke include:
Confusion, delirium, or unconsciousness.
Skin that is red, hot, and dry, even under the armpits.
Avoid strenuous physical activity outdoors during the hottest
part of the day.
Wear light-coloured, loose-fitting clothing to reflect
the sun.
Avoid sudden changes of temperature. Air out a hot car
before getting into it.
If you take diuretics, ask your doctor about taking a lower
dose during hot weather.
Drink 8 to 10 glasses of water per day. Drink even more
if you are working or exercising in hot weather.
If you exercise strenuously in hot weather, drink more
liquid than your thirst seems to require. For example, runners should
drink about 0.25 L (1 cup) of water 10
to 15 minutes before running and another 0.25 L (1 cup) of water every
3.2 km (2 mi) or so.
Get out of the sun to a cool spot, and drink lots of cool
water, a little at a time. If you are nauseated or dizzy, lie down.
If a person's temperature exceeds 38.9°C (102°F),
call for immediate help and try to lower the temperature as quickly as
possible:
Apply cool (not cold) water to the person's whole body;
then fan the person. Or apply ice packs to the groin, neck, and armpits.
Do not immerse the person in ice water.
If you can get the person's temperature down to 38.9°C
(102°F), take care to avoid overcooling. Stop cooling the person
once his or her temperature is lowered to 36.9°C (98.6°F).
Do not give aspirin or
acetaminophen to reduce the temperature.
Watch for signs of heat stroke (confusion or unconsciousness;
red, hot, dry skin).
-
Call 911 or seek emergency care
if the person's body temperature reaches 38.9°C (102°F) and keeps
rising, or
if signs of heat stroke develop:
Confusion, disorientation, unconsciousness.
Skin that is red, hot, and dry, even under the armpits.
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