“First Aid:  Heat Illness”  

By Gary Ramsey, Published in the Adirondack Express on July 15, 2008

 

During the hot summer months illness from over exposure to heat can be a real problem, particularly in those of us over 50, fatigued, out of condition or un-acclimatized to heat. It is important to recognize the various stages of heat illness and take action before it’s too late.

 

Humans have evolved to keep their body temperature within a narrow range where our vital processes work most efficiently -- between about 96 and 102 degrees Fahrenheit. When we burn food for energy, 75% of that energy is turned into heat. If we can’t get rid of excess heat fast enough, the vital organs will begin to “cook.” The circulatory system is the primary mechanism to remove heat. The blood carries excess heat from the organs and muscles to the skin where it forms sweat and evaporates. However, the blood is also needed to deliver food, water and oxygen to the cells. So hot weather requires the circulatory system to do two conflicting jobs -- deliver nutrients and remove heat. On a hot day, when the circulatory system begins this “double duty,” various stages of heat illness may develop.

The least severe is heat syncope or fainting. Even just standing in the heat can cause the internal organs to warm. As they do, the brain tells the circulatory system to extract the heat from the cells and deliver it to the skin surface. As this change over occurs, you may pass out due to a temporary deficiency of oxygen to the brain. Heat syncope is a very mild form of heat illness as is usually self correcting. Moving the person to a shady area or inside and giving them sips of a cool drink will correct the problem.

 

Working hard in the heat can over load the circulatory system. The working muscles are calling for oxygen and water while the vital organs are getting warm and need to be cooled. As the circulatory systems tries to do both jobs, the vital organs may receive a less than adequate blood supply causing headache, nausea and sometimes confusion. Since the working muscles are not getting the water and oxygen they need, there will be an overall feeling of weakness. This condition is called Heat Exhaustion. Due to the intense sweating associated with heat exhaustion dehydration will occur. In addition to moving the person to a cool area you will need to re-hydrate with water and electrolytes. Electrolytes (sodium and potassium) facilitate the movement of water in and out of the body’s cells. A commercial runner’s drink (like Gatorade) is a good choice or you can make your own electrolyte mix with ½ teaspoon of salt (sodium chloride), ½ teaspoon of baking soda (sodium bicarbonate) and ¼ teaspoon of salt substitute (potassium chloride) in approximately one liter of water. Adding electrolytes speeds up the transfer of water in and out of the cells reducing the stress on the circulatory system. As the cooling process evolves, the circulatory system can “catch up” and once again deliver an adequate supply of oxygen rich blood to the organs and the symptoms will subside.

 

Heat cramps are similar to heat exhaustion except just one muscle or muscle group is affected versus an all over effect. As your body works, your muscles demand more water and oxygen. If a particular muscle group is being overused or is constricted in some way (tight clothing, working from an awkward position, etc), the exchange of water and oxygen may not be sufficient causing the muscles to spasm and cramp. First aid for heat cramps is to hydrate with electrolytes, move to a cooler place and stretch (not massage) the affected muscles.

 

If the body core temperature goes above 106 degrees, the temperature control system may fail completely. This a serious condition called heat stroke. The cell membranes begin to “leak” and sodium ions begin to accumulate inside the cells causing a chemical reaction. Chemical reactions produce heat further increasing heat in the organs. As the cells leak, blood volume and flow is reduced. With heat stroke, a vicious circle starts. Leakage causes the cells create more heat while that same leakage also means less blood to deliver the heat to the skin surface. Heat stoke is a true medical emergency. Years ago we used to say the primary sign of heat stroke is very hot and dry skin. This is just not true. A person in the early stages of heat stroke may be exhibiting all the signs and symptoms of heat exhaustion, which includes profuse sweating. The primary way to distinguish heat stoke from heat exhaustion is some sort of behavioral change. This could be in the form of disorientation, aggression and maybe even seizures, malaise or coma. Heat syncope, heat cramps and heat exhaustion can be appropriately treated in the home or work environment. However, if you detect any behavioral change, even if just slight disorientation, you may have the beginning stages of heat stroke. First aid for heat stroke is to call 911 immediately and let the dispatcher know that you suspect heat stoke. With this information, while en route, the EMT’s will begin cooling the ambulance in preparation for transport. While waiting for the ambulance, you need to begin to cool the person right away. The best way to begin the cooling process is to lay the person in a cool water source (bath tub, lake, stream or pool). The water should feel cool to you, but not cold. Water transfers heat 30 times more efficiently than air. However, you will need to swirl the water around the person as their body temperature will heat the water around them quickly. If you don’t have water, you can use ice wrapped in towels and placed against the big veins in the groin, armpit and sides of the neck. Be resourceful. If you don’t have water or ice, use an air conditioned car or fans. Immediate first aid for heat stroke is to begin the cool down process right away.

 

If it’s been very hot for several days, it’s very important to check on the elderly. As we all age, our body functions loose efficiency. If an elderly person can not get relief from the heat, their internal organs may be slowly warming. Over several days, heat stroke could develop. As you check on them, examine their environment and be sure there are adequate cooling mechanisms (shade, fans, air conditioners) available to them. But most importantly, watch for subtle behavior changes. Don’t draw the conclusion that grandpa is just “cranky” from the hot weather. Dig deeper and make sure there isn’t an underlying heat illness developing. If there is any doubt begin to cool the person and seek medical attention.