Handling the heat

Prevention and early intervention are keys to avoiding heat-related illnesses
July 6th, 2016

It may look and feel like a hangover, but it can turn into something much worse.

Each year, about 600 people die from a heat-related illness, such as heat stroke, and thousands more feel the wrath of the body’s inability to cool down property.

“The most effective mechanism to [cool the body] is sweating,” said Dr. Chris Mcstay, chief of clinical operations for Emergency Medicine at University of Colorado Hospital in Aurora and a specialist in wilderness and environmental medicine.

When the body begins to overheat, its defense is to increase blood flow to the skin where it can dissipate heat more easily. Blood vessels near the skin expand and the extra heat causes the body to sweat. That moisture on the skin evaporates, cooling the body.

However, this defense is not as developed in young children and can be weaker in older adults. Children can overheat four times faster than adults. Elderly adults’ bodies — due to age or the effect of certain chronic illness medications — can have weaker cardiac output, which results in a lower cooling defense.

Because of changes in blood flow, people may feel dizziness or headaches as heat-related illnesses, such as heat exhaustion, set in. One can lose consciousness during heat stroke—the most dangerous of heat-related illnesses. Heat stroke is a medical emergency and 911 should be called immediately.

With the onset of heat-related illness, a person can start to feel cool and clammy, even get goosebumps. This happens because blood rising to the skin fails to dissipate heat. This happens mostly in humid climates or where the air is very hot – the air temperature doesn’t allow for the evaporation of sweat to cool the body enough.

An upset stomach and cramps also are signs of early heat-related illness. Dark urine suggests that you are not well hydrated, which can further aid the onset of heat exhaustion and stroke. In dry regions, such as Colorado, sweat may evaporate so quickly that people doesn’t realize how much they are sweating and therefore, don’t realize how much fluid is needed to replenish the body.

“You need to drink and stay on top of your thirst,” Mcstay said. “You should be peeing regularly, and it should be clearer than a dark yellow color.”

Although water is good, water alone can get a dehydrated person into trouble, he added. The blood carries salt and too much water can dilute that salt. When a person’s sodium levels drop too much, it can cause seizures. Mcstay recommends eating food along with drinking water, or drinking energy drinks that contain minerals the body needs.

When the body becomes extremely hot — heat stroke is considered to begin at a temperature of 104 degrees Fahrenheit — it begins to denature and destroy proteins, which has a wide range of effects from failed kidneys to brain damage. It can take only 10 minutes for body temperature to rise to 104 or even higher, he said.

“For example, a kid who is left in a car, their temperature can reach 108 very quickly and they can die,” Mcstay said. “When it’s really hot outside, the body can only absorb so much.”

Each year, about 35 children die of heat-related illnesses while left in parked vehicles, according to the National Safety Council.  Even when the temperature doesn’t seem extreme, children die when left in a hot car. In 2015, 16 children ages 4 months to 3 years died in vehicles while outside temperatures ranged from 52 to 96 degrees. A 14-month-old child who died in 50-degree outside temperatures was left in the vehicle while the heater was running.

Elderly people, especially those without air conditioning, are also common victims of the heat. Along with their weaker bodies, they often live alone and heat-related illnesses strike when there is no one around to help or recognize the symptoms.

“There needs to be that element of being neighborly when it comes to prevention,” Mcstay said. “We need to look after each other.”

Earlier this summer, when temperatures across Colorado reached into the 100s, UCHealth’s emergency rooms in northern Colorado saw about one person per day for heat-related illnesses.

Heat stroke is a medical emergency, explained Dr. Jamie Teumer, UCHealth ER director for northern Colorado. People should call 911 immediately when body temperatures rise to 104 or greater.

But no matter if it’s heat stroke or a lesser life-threatening heat-related illness, the interventions are the same.