July 16, 2018

Cars turn deadly in summer heat

It is never safe to leave children or pets in parked cars.

The high temperatures of summer turn cars into ovens in a matter of minutes.

Roughly 37 children die every year in hot cars, according to the safety organization Kids and Cars. 2018 was the deadliest on record, with 52 hot car fatalities in the United States. And parents who think they could never possibly forget their child in the car should think again.

"It is very important to always check the back seat of the car, and to look before you lock," said Shannon Garton, MD, family medicine physician at Kaiser Permanente's Edwards Medical Offices in Edwards, Colorado. "Parents can have a change in routine, or be stressed or busy, so while it may seem impossible to forget a child is in a car, it does happen."

Research shows that habits, such as driving from home to work every day, interfere with brain functioning when there's a change to the routine. Forgotten Baby Syndrome is a result of the brain's ability to allow you to do things without thinking about them, according to published interviews with David Diamond, a professor at the University of South Florida who has been studying Forgotten Baby Syndrome since 2004.

Why children are so at risk

On a 90-degree day, the temperature inside a car can reach 160 degrees in 10 minutes, Dr. Garton said. Rolling down the windows doesn't help, and a car's oven-like heat can develop on cooler days, too.

"It is never safe to leave a child or a pet in a car," she said.

Children, and especially infants, are more prone to have heat exhaustion or heat stroke because they have fewer sweat glands and are not as able to adapt as quickly to the temperature, Dr. Garton said. A child's temperature can rise up to five times faster than an adult's, and pets also cannot tolerate hot temperatures as well as adult humans.

"On a day when the outside temperature is 80–100 degrees, the interior of a car can reach 130–170, and the majority of this temperature rise occurs during the first 15 minutes," Dr. Garton said.

There have also been numerous cases in which curious young children climb into a car on their own without their parents' knowledge.

"If a child is missing, checking all compartments of a car is one important place to look, even if the car is locked," she said.

The body's response to heat

Heat stroke, which is the main killer of children in hot cars, is the most severe reaction the body has to heat. Signs include hot, flushed skin with a high fever over 105 degrees, Dr. Garton said, adding that a rectal temperature is more accurate than an oral temperature in these cases.

"50% of children with heat stroke do not sweat," she said. "Heat stroke can cause confusion, coma, or shock."

Any sort of exposure to heat can cause these kinds of reactions in the body. Exercising in the heat, for example, can increase the risk for these symptoms, especially if a person is not well-hydrated, Dr. Garton said.

Other physiologic responses to heat include cramping in the calf, thighs, or stomach, all of which are signs of dehydration. Heat exhaustion is characterized by pale skin, profuse sweating, and nausea, and can also include dizziness, fainting, or weakness.

"A person can progress from heat exhaustion to heat stroke. Again, with heat exhaustion, it is very important to hydrate, get into a cooler place, and rest," Dr. Garton said. "If at any time a patient is not able to adequately hydrate orally due to nausea, listlessness, or vomiting, it is important to seek medical care to get IV hydration."

Because children are often unable to verbalize their symptoms, look for warning signs such as listlessness and pale or beet-red skin that is hot to the touch.

"If you are concerned that your child is suffering a reaction to the heat, and especially if they are not able to appropriately hydrate on their own, seek immediate medical attention," Dr. Garton said.

A dog inside a locked car

Look before you lock

Parents and caregivers should take the following steps to prevent heat stroke tragedies:

  • Look before you lock and get into the habit of checking the back seat before leaving your vehicle.
  • Put something you’ll need, such as a cell phone or wallet, in the back seat.
  • Keep a large stuffed animal in the child’s car seat. When the child is in the seat, place the animal in the front seat as a visual reminder that the child is in the car.
  • Keep cars locked at all times and keep keys out of reach of children.
  • Use drive-through services when available and pay for gas at the pump.