It was the type of day that could wilt a metal gatepost.”

Colin Cotterill, Thirty-Three Teeth

When the star Sirius (the “Dog Star” of the Canis Major constellation) appeared just before sunrise, the Greeks and Romans called it thedog days”. The “dog days” of summer were synonymous with the hottest days of the year and associated with short tempters, fevers, and catastrophes.

The key to successfully managing the hottest days of summer is being aware of the heat’s impact and adjusting to minimize the risk.

While the ambient temperature is important (thermometer temperature), the heat index is more important. The heat index — “real feel temperature” — is what the temperature feels like to the human body when humidity is combined with the air temperature.  The importance of heat index is the impact on the human body’s comfort.  When the body gets too hot, it begins compensating (perspire or sweat) in an attempt to cool itself off.  As perspiration evaporates, the body cools thereby regulating its temperature. When the atmospheric moisture or humidity is high, the rate of evaporation from the body decreases and the body cannot cool itself. There is an inverse relationship between the heat index and the body’s ability to cool itself — as heat index goes up, the body’s ability to cool itself goes down.

It is important to remember:

  • A person can feel the effects of heat related illness quickly and with little warning.
  • Some persons are at a greater risk of heat related illnesses: young children, older adults, persons with chronic illness, and persons acute illness or overweight.

Avoiding heat related illnesses in the summer can be challenging for the body. Consider a juggler. If the juggler is only juggling one ball, the likelihood of success is good. As the juggler adds more balls the difficulty increases. If we put that juggler on a ball, the difficulty increases significantly. Anything unexpected will most likely result in a juggling disaster. This is what dealing with extreme temperatures is similar to. Most of us can begrudgingly deal with the heat. Adding a chronic illness, an additional health condition or health complication(s) with the heat and the difficulty of success will be high and potentially hazardous.

Extreme heat — especially during physical activity — can make staying cool difficult. Add cardiovascular disease and the heart increases it’s workload. As blood moves toward the skin to support the body’s cooling response, the heart beats faster and pumps with greater force. A history of diabetes may be accompanied by complications that impair the bodys ability to sweat. The inability to sweat combined with the extra work of the cardiovascular system creates the perfect storm that triggers a chain of events that complicate health management and support an unfavorable outcome.

Even the task of staying hydrated can be difficult for persons with heart disease where there’s a balance of avoiding irregular heart rates associated with dehydration, fluid overload in the face of congestive heart failure, and the balance of electrolytes that regulate everything from kidneys to heart function. For persons with diabetes, elevated glucose levels in extreme heat could increase the risk of dehydration as the body tries to lower glucose levels through frequent urination. As a large percentage of persons living with diabetes also have some degree of heart disease, the potential for a perfect storm is real and should be taken seriously.

So the best recommendations for avoiding heat related illnesses while living with a chronic illness come down to (1) avoiding activities in extreme heat when possible and (2) dress appropriately for the summer to promote cooling.

If avoiding the heat is not an option, there are things that can reduce the likelihood of heat related illness:

  • Find an escape from the heat. Remember air conditioning not only cools the air but removes some of the moisture in the air also allowing any perspiration to evaporate. Find places in your community where you can go to get cool. Libraries, shopping malls and community cooling centers can provide a cool place to take a break from the heat.
  • Keep your home cool:
    • Cover windows with drapes or shades.
    • Weather-strip doors and windows.
    • Use window reflectors, such as aluminum foil-covered cardboard or automobile window shades to reflect heat back outside.
    • Add insulation to keep the heat out.
    • Use attic fans to clear hot air out of the building.
    • Install window air conditioners and insulate around them.
  • Avoid high-energy or strenuous activities. If youre outside, find shade. Wear a hat wide enough to protect your face. Break the activity into smaller time periods allowing breaks to cool down and rehydrate. Remember that while working in a hot area with an electric fan may move the air, in near 100 degree real feel” temperatures, it could give a a false sense of comfort on the outside while not allowing the core body” temperature to cool down compromising safety.
  • Wear clothing that is loose fitting, lightweight, and light-colored clothing.
  • Drink plenty of fluids to stay hydrated. If you or someone you care for is on a special diet, ask a doctor for resources how best to accommodate it. The number one question my patients ask, how much water is enough?” Any one who runs, hikes or camps out has probably heard the darker the urine, the more water you need to drink.” Begin drinking water BEFORE you anticipate needing it rather than trying to “catch up” to dehydration after the fact.
  • Never leave a child, a disabled adult or animal alone inside a vehicle. The National Weather Service warns against this even in the winter. Interior heat can increase to deadly temperatures in a matter of minutes. If your car is parked in the drive-way, lock the doors to prevent a young child from climbing inside unaware of the potential dangers. Additionally, remember to check-on family members and neighbors for signs of weather-related illness.

Most importantly learn to recognize the signs of heat-related illness and how to respond to it:

  • Heat cramps: Muscle pains or spasms in the stomach, arms or legs. Response: Go to a cooler location. Remove excess clothing. Take sips of cool sports drinks with electrolytes. Get medical help if cramps last more than an hour.
  • Heat exhaustion: Heavy sweating, paleness, muscle cramps, tiredness, weakness, dizziness, headache, fainting, nausea, vomiting. Response:Go to an air-conditioned place and lie down. Loosen or remove clothing. Take a cool bath. Take sips of cool sports drinks with salt and sugar. Get medical help if symptoms get worse or last more than an hour.
  • Heat stroke: Extremely high body temperature (above 103 degrees); red, hot and dry skin without sweat; fast, strong pulse; and/or dizziness, confusion or unconsciousness. Response: Call 9-1-1 or get the person to a hospital immediately. Cool down with whatever methods are available until medical help arrives.
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No one plans to “over do it” and find themselves in a weather related emergency. Be aware of potential hazards and be ready to act if necessary.