
Hyperthermia: Too Hot for Your Health
Irene is retired, she loves to
work in her garden. Because she has always spent hours outside, she thinks the
heat and humidity of Midwestern summers don't bother her. Then last year an
unusual heat wave hit her area. Every day the temperature was over 100° F, and
the humidity was at least 90%. Five days into the heat wave, her daughter Kim
came over because Irene sounded confused on the phone. Kim found her mom passed
out on the kitchen floor. The ambulance came quickly when called, but Irene
almost died. She had heat stroke, the most
serious form of hyperthermia.
Almost every summer there is a deadly heat wave in some
part of the country. Too much heat is not safe for anyone. It is even riskier if
you are older or if you have health problems. It is important to get relief from
the heat quickly. If not, you might begin to feel confused or faint. Your heart
could become stressed, and maybe stop beating.
Your body is always working to keep a balance between
how much heat it makes and how much it loses. Your brain is the thermostat. It sends and receives
signals to and from parts of your body that affect temperature, such as the
spinal cord, muscles,
blood vessels, skin, and glands that make substances known as hormones. Too much
heat causes sweating. When the sweat dries from your skin,
the surface of your body cools and your temperature goes down.
Being hot for too long can cause many illnesses, all grouped under the name
hyperthermia (hy-per-ther-mee-uh):
- Heat cramps are the
painful tightening of muscles in your stomach area, arms, or legs. Cramps can
result from hard work or exercise. While your body temperature and pulse
usually stay normal during heat cramps, your skin may feel moist and cool.
Take these cramps as a sign that you are too
hot - find a way to cool your body down. Be sure to drink plenty of fluids,
but not those containing alcohol or caffeine. For more,
please read the Heat
Cramps
article.
- Heat edema is a swelling
in your ankles and feet when you get hot. Putting your legs up should help. If
that doesn't work fairly quickly, check with your doctor.
- Heat syncope is a sudden dizziness that may
come on when you are active in the heat. If you take a form of heart
medication known as a beta blocker or are not used to hot weather, you are
even more likely to feel faint when in the heat. Putting your legs up and
resting in a cool place should make the dizzy feeling go away.
- Heat exhaustion
is a warning that your body can no longer keep itself cool. You might feel
thirsty, dizzy, weak, uncoordinated, nauseated, and sweat a lot. Your body
temperature stays normal, skin feels cold and clammy. Your pulse can be normal
or raised. Resting in a cool place, drinking plenty of fluids, and getting
medical care should help you feel better soon. If not, this condition can
progress to heat stroke. For more, please read the Heat Exhaustion article.
- Heat stroke is an
emergency - it can be life threatening! You need to get medical help right
away. Getting to a cool place is very important, but so is treatment by a
doctor. Many people die of heat stroke each year. Older people living in homes
or apartments without air conditioning or good airflow are at most risk. So
are people who don't drink enough water or those with chronic diseases or alcoholism. For
more, please read the Heat
Stroke
article.
The Signs of Heat Stroke
- Fainting, possibly
the first sign,
- Body temperature over 104° F,
- A change in behavior - confusion, being grouchy,
acting strangely, or staggering,
- Dry flushed skin and a strong rapid pulse or a slow
weak pulse,
- Not sweating, despite the heat, acting delirious, or being in a coma.
Who Is at Risk?
Hundreds of people die from hyperthermia each year during very hot weather.
Most are over 50 years old. The temperature outside or inside does not have to
hit 100° F for you to be at risk for a heat-related illness. Health problems
that put you at risk include:
- Heart or blood vessel problems, poorly working sweat
glands, or changes in your skin caused by normal aging.
- Heart, lung, or kidney disease, as well as any
illness that makes you feel weak all over or causes a fever.
- High blood pressure or other conditions that make it
necessary for you to change some of the foods you eat. For example, if you are
supposed to avoid salt in your food, your risk of heat-related illness may be
higher. Check with your doctor.
- Conditions treated by drugs such as diuretics,
sedatives, tranquilizers, and some heart and blood pressure medicines. These
may make it harder for your body to cool itself by perspiring.
- Taking several drugs for a variety of health
problems. Keep taking your prescriptions, but ask your doctor what to do if
the drugs you are taking make you more likely to become overheated.
- Being quite a bit overweight or
underweight.
- Drinking alcoholic beverages.