News Release

Even in the Amazon jungles, treatment for heat exhaustion is the same as it is right here at home

Peer-Reviewed Publication

Cedars-Sinai Medical Center

LOS ANGELES (August 18, 1999) -- If you're going to be sitting in a metal boat on a sun-drenched lake an hour's hike from the Amazon River, it's a good idea to take along plenty of fluids and possibly a doctor or two.

"It's hot and very humid. It's hard to get a good evaporative cooling process going," says Mary L. Hardy, M.D., director of the Integrative Medicine Medical Group at Cedars-Sinai Medical Center, a program that integrates Western medical practice with botanical medicine, traditional Chinese approaches, acupuncture and other alternative therapies. Dr. Hardy has studied traditional healing systems in Kenya and China, as well as in Peru. A board-certified specialist in internal medicine, she journeyed into Peru five years ago with a group of researchers studying botanical medicine and traditional healing systems and practices.

"It's not so bad in the jungle because you have a lot of shade but in this open, metal boat, we were all really sweating. On the hike back, one of the members, a pharmacist I was hiking with, suddenly got very sick, was throwing up and appeared flushed. She was normally a very pale person so it was very clear that she had heat exhaustion. We had to quickly figure out how to take care of her so we wouldn't have to carry her out."

One team member contributed a powdered sport drink and Dr. Hardy added oral rehydration salt from her emergency kit. "We made a salty drink and gave her small sips because if you give too much, the sufferer will throw it right back up. We moistened a bandana with water, added a little bit of lavender/peppermint oil to make it even a little bit more cooling, and put that on the back of her neck, along with one on her face. Then we fanned her. In about 15 or 20 minutes, she was able to walk again."

"For the trip down the Amazon, I had two medical kits," she says. "I still take two with me, one with natural medicines and one with pharmaceuticals, so that I'm prepared for anything that comes along. Luckily, there's a physician not too far from where we go, so if something really bad happens, we have backup."

Whether you plan to trek through the Peruvian Amazon or ride a bike on a sunny day in Los Angeles, Dr. Hardy says preparing yourself ahead of time for the heat is the most important preventive measure you can take.

But if you're in the heat longer than expected, you're exercising beyond your level of safety, or you have a medical condition that makes you susceptible, know the symptoms of heat exhaustion and take immediate action if needed. Failure to do so can push your body into heatstroke, requires professional, emergency intervention and can be fatal.

BEFORE GOING OUT:

  1. Don't eat a heavy meal of high-fat foods.
  2. Do eat light foods that are easily digested. Include only small amounts of protein.
  3. Do drink plenty of water and a sport drink to be sure your fluids and minerals are in good shape before you leave home. Add a little vitamin C or drink a glass of diluted fruit juice containing vitamin C to increase your level of antioxidants, which help protect cells and muscles from damage.
  4. Avoid alcohol and caffeine, which can contribute to dehydration.
  5. Avoid carbonated beverages, which tend to be highly acidic and contain too much sugar.
  6. Wear loose, light-colored clothing that will help reflect the sun and allow perspiration on your skin to evaporate.
  7. Use and take along a sunscreen. Getting a sunburn will impair your ability to dissipate heat.

WHILE THE HEAT IS ON
Sweating is your body's natural attempt to maintain normal body temperature. The evaporation of sweat cools your skin. Therefore, your two goals in avoiding heat exhaustion are to continually replace the fluids that are being lost through sweat while optimizing conditions that allow sweat to evaporate. Humidity reduces evaporation, reducing your body's ability to cool itself. The use of a fan can help increase evaporation.

Sweat contains minerals, including sodium, potassium and magnesium, that your body needs. But Dr. Hardy says many people make the mistake of replacing sweat with water or juice that do not replenish these necessary nutrients. She suggests drinking a sport drink that contains about 100 milligrams of sodium and potassium per serving and about 25 milligrams of magnesium per serving. Regardless of the exact amounts, most powders or pre-mixed sport drinks should be adequate for routine activity.

She also recommends checking to be sure a sport drink contains a sugar source, such as glucose or fructose, and that it has vitamin C. "You might have a drink that contains about 100 or 200 milligrams of Vitamin C in it or you can mix your drink with fruit juice or put some vitamin C powder in it."

If you get into a situation where you're overheating and you don't have a replenishing drink handy, dilute some fruit juice with water and put a little bit of salt in it, suggests Dr. Hardy. It should taste slightly salty.

THE SYMPTOMS OF HEAT EXHAUSTION AND HEADSTROKE
Watch for the symptoms of heat exhaustion: The skin may become cool, moist, pale or flushed, accompanied by heavy sweating, headache, nausea or vomiting. You may become dizzy and exhausted to the point of collapse.

The elderly and people with pre-existing medical conditions are especially susceptible. Many disorders and medications to treat disorders can interfere with dissipation of heat. For example, diuretics, medications taken to increase urine output, can decrease a patient's sodium level, complicating the effort to maintain electrolyte balance. Antihistamines taken to counter allergies also can cause problems of fluid absorption and output.

Little children are at increased risk, too, says Dr. Hardy, because they can't complain, their skin is very sensitive to sunburn, and they have a small body mass, making it harder for their bodies to regulate heat. "You have to be real attentive and if the baby is more listless than usual, he or she may need some diluted apple juice with a little pinch of salt."

If heat exhaustion is not treated, it may lead to heatstroke: Your face will be flushed, skin will be hot and dry, and sweating will stop as body temperature rises. Headache, nausea and dizziness will progress to confusion, delirium, shock, coma and even death. Emergency assistance should be called as quickly as possible. If you're with someone who is suffering from heatstroke, soak the victim in cool water if possible or wrap the victim in a cool, wet sheet in the shade while waiting for help to arrive.

TREATMENTS
According to Dr. Hardy, most of the symptoms of heat exhaustion and heatstroke result from three events. Excessive loss of fluid leads to a reduced amount of blood circulating to your working muscles and the rest of your body, including your brain. Even a one percent loss of volume can begin to cause problems. A low blood sodium level can lead to brain swelling and neurological symptoms. And low mineral levels trigger muscle cramping and other physical symptoms.

"The sodium, volume and mineral depletion cause most of the symptoms and then the body's core temperature goes up," says Dr. Hardy. "Your regular ways to get rid of heat -- flushing and sweating -- are no longer effective and you're crossing the border from heat exhaustion to heatstroke. It's serious."

Several homeopathic preparations, including belladonna and glonoine, may be used to treat the symptoms of heat exhaustion, but Dr. Hardy recommends that anyone -- especially those with medical conditions -- consult a physician or health-care provider first. Glonoine is a form of nitroglycerin, which should be used with caution by anyone with a heart problem, for example.

"These are things that people should talk to their physicians or trusted medical advisers about to find out if these substances are appropriate for them to use," says Dr. Hardy.

She says that whether a health-care provider's approach is Eastern, Western or 'alternative,' the treatments for heat-related illnesses are essentially the same: rest, adequate cooling, fluid replacement and mineral replacement.

Dr. Hardy is a member of the American Botanical Society and the American Holistic Medical Association. She serves on the advisory board of the National College of Phytotherapy and on the board of the Institute of Medical Herbalism. She received her medical degree from Louisiana State University in New Orleans and completed her internal medicine residency at Tuft's New England Medical Center in Boston. Cedars-Sinai's Integrative Medicine Medical Group began seeing patients at the beginning of this year.

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