FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

HEAT-RELATED ILLNESS STRIKES READER AND DOC WOLF THIS SUMMER

Question: During the last hot spell we had a few weeks ago, I spent several hours mowing our large lawn, and as I started back to the house after putting the lawnmower away, I collapsed. My wife took me to the emergency room, where the doctors said I had heat stroke. I've now recovered and feel fine, but I want to make sure I don't have this problem again. What precautions should I take?

Answer: Our organs operate efficiently in a very narrow range of temperatures, about 98 to 100 degrees Fahrenheit. The reason we can function well in a wide variety of environments from cold winter weather to the heat of summer is that the human body has effective methods for controlling the temperature of the organs in the head, chest and abdomen.

In a warm environment, the body generates more heat than it needs to keep the organs at their optimal working temperature. The body deals with this situation by pumping the warmed blood to areas where its heat can be released to the environment. This is why on a hot day you become "flushed" as the circulation in the blood vessels close to the surface of the skin is increased. Not only is the blood close to the surface, but as I'm sure you know the temperature exchange is augmented by the cooling effect of evaporation of sweat from the skin.

Normally these and other temperature-control mechanisms, including air exchange in the lungs, do a satisfactory job. In some situations, however, these methods may not be sufficient to keep the body temperature down where it belongs. Prolonged exercise while in bright sunlight on a hot summer day such as you experienced while mowing your lawn is one of these situations.

If the internal temperature of the body increases above the optimal level, the body's organs start to work less efficiently, and this can produce telltale symptoms. A mild elevation, say to a temperature of 101 or 102, causes some general muscle weakness, nausea, headaches, dizziness, muscle cramps and clammy skin. This milder form of heat-related illness is called heat exhaustion.

Earlier this summer, I and a friend of mine developed these heat exhaustion symptoms while building a small storage barn in my yard. We were determined to finish the job even though we were hot and tired. Fortunately, after fluids and a day of rest the usual treatment for heat exhaustion we were both "good as new."

In the most extreme cases of heat illness, the internal temperature may reach 105 to 107 degrees and cause serious damage to the liver, kidneys, brain and heart. This is called heat stroke, just as you had, and it may be fatal without immediate medical intervention. You were lucky your wife and son acted so promptly.

This is an important point for all my readers to understand. The best thing to do when you think someone has heat stroke is to call emergency medical services immediately. While waiting for the ambulance to arrive, move the victim into the shade. It will help lower the body temperature if you spray his or her bare head, chest and abdomen with cool but not cold water. Offer liquids to drink if the person is able, but above all else, get emergency help as quickly as humanly possible!

As in most situations, prevention of a heat related illness is the best approach. To avoid getting into trouble this summer, I'd suggest that when you are working outside you take frequent breaks even if the job is almost done to get out of the direct sunlight and drink large amounts of liquid.

I'll listen to my own advice next time!

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.