Beating the Heat
As summer temperatures climb into the 90s, older people are in danger of conditions caused by extreme heat, such as dehydration and hyperthermia, which can lead to heat exhaustion and its most serious form, heat stroke.
Every summer as temperatures and humidity indices rise, I flash back to long ago in the summer of 1995. Back then I was the chief resident for the department of internal medicine at the University of Chicago Hospital, and I was steeling myself for the challenges of welcoming and supervising the newest cadre of recently degreed medical interns coming to our hospital.
Little did I know how quickly we would be tested beyond anything we could have anticipated. In his book, Heat Wave: A Social Autopsy of Disaster in Chicago, Eric Klinenberg sets the scene:
“On Thursday, July 13, 1995, Chicagoans awoke to a blistering day on which the temperature would reach 106 degrees. The heat index, which measures how the temperature actually feels on the body, would hit 126 degrees by the time the day was over. Meteorologists had been warning residents about a two-day heat wave, but these temperatures did not end that quickly. When the heat wave broke a week later, city streets had buckled; the records for electrical use were shattered; and power grids had failed, leaving residents without electricity for up to two days. And by July 20, more than 700 people had perished — more than twice the number who died in the Chicago Fire of 1871 and 20 times the number of those struck by Hurricane Andrew in 1992 — in the great Chicago heat wave, one of the deadliest in American history.”
Two of the critical factors that cause injury and death in such a heat wave are dehydration and hyperthermia, and elderly patients are at increased risk for both conditions. To keep a person’s internal temperature at 98.6, the body is in a state known as “homeostasis,” which means the body’s physiological checks and balances are functioning properly in relation to each other. A key and nearly universal change that comes as part of the aging process, however, is that this homeostatic process becomes a little bit slower and less reactive, and therefore less able to respond rapidly to a change in the outside environment such as a heat wave.
The result is that as people age, they are more prone to heat stress:
An older body does not adjust as well as a younger body to sudden changes in temperature.
Older adults may not “feel” hot even when their temperature is dangerously high.
Older adults are more likely to have a chronic medical condition, such as thyroid or vascular disease, that changes the body’s normal responses to high heat.
Older adults are more likely to take prescription medicines that impair the body's ability to regulate its temperature, or inhibit a person’s ability to sweat, or blunt a response to developing dehydration.
When temperatures get above 90 degrees Fahrenheit, caregivers should check on their loved ones and take actions that could include several strategies.
Drink Up!
As we get older our body’s need for water increases right alongside the risk of dehydration. It’s a bad combination.
So go get yourself a glass of water… and then read the rest of this article.
Believe it or not, the human body is about 60% water! Every system in the body depends on water to function properly. For example, water flushes toxins out of vital organs, carries nutrients to cells, and provides a moist environment for ear, nose and throat tissues. On a daily basis 2-3 liters are lost each day mostly from perspiration, urine and bowel movements. Lack of water intake to replace what is lost can lead to dehydration, a condition that occurs when you don't have enough water in your body to carry out normal functions.
As we age, there are some key changes in our bodies that affect water intake and make us more prone to dehydration.
Older adults get thirsty less. The main signal for needing to take a drink is diminished.
Older adults need just as much water. Those of us in the south need to be particularly cautious about this since our climate creates greater losses of water each day through perspiration.
Certain medications and medical conditions can cause or worsen dehydration. Talk to your physician if you have questions about this.
The Institute of Medicine advises that men consume about 13 cups of total beverages a day and women consume about 9 cups of total beverages a day. For most of us following the “8 x 8 rule” of 8 glasses of 8 ounces per day is a good start. You can also monitor your urine output and observe the color of your urine — a light yellow color is a good sign you’re drinking enough water. If it’s darker yellow, you probably need to drink more.
Another way to estimate your daily water needs is to aim for 1/2 your weight in pounds equaling consuming that same amount of water in ounces. That is, if you weigh 200 pounds, you should drink 100 ounces of water per day.
Note: This is a general rule of thumb, but ask your personal physician what they recommend for you, as many medical conditions and medications can impact water intake requirements.
Keep in mind that food usually accounts for 20 percent of your total fluid intake. Many fruits and vegetables, such as watermelon and cucumbers, are nearly 100 percent water by weight so keep a steady supply in your diet.
Beverages such as milk and juice are also comprised mostly of water. Even beer, wine, and non-caffeinated beverages such as coffee, tea or soda can contribute to your total. But keep in mind that caffeine and alcohol are dehydrating agents, so they work against keeping yourself hydrated.
Here are some tips on how to keep hydrated:
You need to replenish daily but you can “fill the tank” at the most convenient time.
You can drink most of your water early in the day when you are going to be home and near a bathroom, and thus avoid needing trips to bathrooms while away from home or during the night.
You can also “eat” your water: Watermelon, grapes, and cucumbers are good sources of water.
Any water-based beverage that does NOT contain caffeine or alcohol can count toward your water intake — even soup! (Caffeine and alcohol are natural diuretics and so will make you lose water.)
Drinking a beverage using a straw often increases total fluid intake.
Add ice to your drinks, and you will get a bit more water as the ice melts.
Also see How to Stay Hydrated
Keep Your Cool
Another important change of aging you need to know about is that older people may not feel hot when the temperature is dangerously high. Even temperatures in the low 90s can be dangerous for older adults. With our average temperatures hitting 90s in June, July, and August we need to be ever vigilant here in Central Florida.
Turn on the air conditioning — or take your loved one somewhere that is air-conditioned, such as a shopping mall, grocery store, senior center, movie theatre, museum, or library. (Turning on a fan will not be effective at cooling down an older adult.)
Take cool showers, baths, or sponge baths.
Wear lightweight, light-colored, loose-fitting clothing. Clothes made of light-weight cotton are a good choice.
Stay out of the sun and wear a hat if you do go out.
Avoid exercising outdoors if the temperature is 90 degree or higher. Instead, adjust the time of your exercise to early morning or later in the day, to avoid the high heat. Or try exercising in an air-conditioned area, such as walking around a mall, cruising the grocery store aisle, or swimming in an indoor pool.
Emergency Care
Signs of someone suffering from heat stress include weakness, headaches, dizziness, cramps, or a rising body temperature. If you feel that someone may be suffering from overheating, you may be dealing with a life-threatening emergency. Have someone call for immediate medical assistance while you begin cooling the affected person. Do the following:
Get the person out of the sun and into a shady area.
Cool the person using whatever methods you can. For example, immerse the person in a tub of cool water; place the person in a cool shower; spray the person with cool water from a garden hose; sponge the person with cool water; or if the humidity is low, wrap the person in a cool, wet sheet and fan him or her vigorously.
Monitor body temperature and continue cooling efforts until the body temperature drops to 101°–102°F.
If emergency medical personnel are delayed, call the hospital emergency room for further instructions.
Do not give the person alcohol to drink.
Get medical assistance as soon as possible.
