Heat Exhaustion and Heat Stroke: What’s the Difference?

Daily Health Solutions, Featured Article, Healthy Heart, Healthy Living, Stroke
on July 4, 2013
The difference between heat stroke and heat exhaustion.

Who doesn’t love playing outside in the summer? The problem is that some of us love it so much that we can get carried away and allow heat’s effects to sneak up on us, resulting in heat exhaustion, or even heat stroke.

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How do you know when your body temperature’s a cause for concern? And how do you keep from getting to that point? Here’s expert advice for distinguish between heat exhaustion and heat stroke, and ways to treat and prevent both.

Heat Exhaustion

What it is: “Heat exhaustion comes when your body gets overheated, and you are no longer able to sweat, and you get sick from dehydration,” says Dr. Jeff Kalina, associate director of emergency medicine at the Methodist Hospital in Houston. The excessive exposure to heat typically leads to a loss of fluids and electrolytes, the salts and minerals that conduct electrical impulses that operate your nerves, heart and muscles.

Signs: Signs include fatigue, dehydration, dizziness, headache, nausea, sweating and concentrated (dark yellow) urine, says Andy Jean-Jacques, director of nursing at Trinity Healthcare Services in West Palm Beach, Fla.

Treatment: To treat heat exhaustion, rest in the shade to cool off and rehydrate with water or an electrolyte-replacing fluid like a sports drink as soon as possible, says Kalina.

Prevention: Hydrate before you go outside, says Kalina. “Drink enough water or  [sports drink] so that you are urinating every couple of hours.”  If you are not urinating or the urine is dark yellow, you are not drinking enough, he says. Avoid alcohol, which promotes dehydration, and wear loose-fitting layers in moisture-wicking fabrics and hats to shade you from the heat. “Wicking material evaporates sweat best,” Kalina says. Make sure you wear a sunscreen that blocks ultra-violets rays, he adds, which heat up the body.

Heat Stroke

What it is: Heat stroke is more serious and less common than heat exhaustion, says Kalina. It occurs when the brain is no longer able to regulate body temperature your core temperature reaches 104 or 105 degrees. “You start to get muscle breakdown, kidney dysfunction and ultimately brain dysfunction due to dehydration and heat,” he says. “It is considered a medical emergency and can be fatal.”

Signs: “You can have stroke-like symptoms such as severe confusion, delirium, paralysis and even death,” says Kalina. “You may be unable to move, have slurred speech, a loss of vision or a seizure.”

Treatment: “You need to be treated as soon as possible,” says Jean-Jacques.  If you suspect someone has had a heat stroke, call 911: “Remove the person from the heat immediately to air-conditioning, if possible. Cool down the person by applying cold water to the body and removing any tight clothes.”

Once someone with heat stroke arrives at the ER, doctors place ice bags on the groin and armpits, where the big blood vessels are, says Kalina. The patient is likely covered with a cool air-infused cooling blanket, sprayed with water, and intravenously given cold liquids with electrolytes. “In extreme cases, we may put a catheter in the abdominal cavity, infusing it with cold fluid to cool the organs.  We may also put tubes in the person’s chest and put in cool water to cool the heart and organs. ”

Prevention: Prevent heat stroke the same way as you prevent heat exhaustion, says Kalina: Begin drinking water before you go out in the sun and continue drinking throughout your outdoor play. Dress in loose, cool, light-colored clothing and a hat, and wear plenty of UV protective sunscreen.

There are also some medications that are dehydrating, like diuretics, blood pressure medications, antihistamines, and some antidepressants.  “Talk to your doctor about dehydrating medications and how you can protect yourself from the heat,” says Kalina.