UI Hospitals and Clinics

News Article

Beat the Heat

Temperatures in Iowa continue to hover in the high 90s and the heat indices are pushing triple digits. It's hot!

University of Iowa Health Care emergency medicine experts warn that the current high temperatures can pose serious health risks and urge people to be on the lookout for signs of heat-related illness in themselves and others.

"The biggest thing, in my opinion, is prevention," says Azeemuddin Ahmed, MD, UI clinical associate professor of emergency medicine. "The best way to avoid heat-related illness is not to let it start in the first place, and that means that people need to stay hydrated, seek shade or cool down periodically, and wear lighter colors when they're outside.

"It's also a question of awareness," he continues. "Heat-related illness can progress quite quickly if you don't intervene. If you start to feel ill – excessively fatigued, nauseous or dizzy, or you get a headache – you need to cool off and get rehydrated right away."

Heat-related illnesses span a range of severity from prickly heat to heat exhaustion to heatstroke, which is a true medical emergency that can quickly lead to permanent brain damage, widespread organ failure, or even death if not reversed.

Heatstroke occurs when a person's core temperature rises above 105 degrees, they stop producing sweat, and they have neurological symptoms, including disorientation, hallucinations, seizures or coma, explains Andrew Nugent, MD, UI clinical professor and chair of emergency medicine. Nugent echoes Ahmed's advice in listing the best ways to prevent heatstroke: drink lots of fluids (water or sports drinks are best, but not alcohol, which dehydrates), decrease activity levels, and take frequent breaks from the sun and the heat.

In hot weather, human bodies have two main cooling mechanisms. Blood flow to the skin increases, giving you that flushed look but allowing the blood to cool by heat transfer to the air. Increased sweating also produces a cooling effect as the sweat evaporates from the skin. Unfortunately, if the air temperature is too high, heat transfer doesn't work, and high humidity can prevent sweat from evaporating efficiently.

Some medications can also interfere with the body's ability to tolerate temperature extremes. For example, some blood pressure medications can mask the symptoms of heat-related illness or contribute to dehydration, says Ahmed.

If the body cannot get rid of excess heat, it will store it, causing the body's core temperature to rise, heart rate to increase, and launching the onset of increasingly severe symptoms.

Because the body's main cooling mechanisms don't work as well in young kids or older adults, the very young and the very old are particularly susceptible to the ill effects of heat, notes Charles Jennissen, MD, UI clinical associate professor of pediatrics and emergency medicine. And, while most adults seek shade or air conditioning and take it easy when it's too hot outside, kids tend to play as usual and often don't stop for frequent water breaks.

"Kids can get themselves into trouble with heat-related illness because they don't slow down when it gets hot," Jennissen says. "It's really important for caregivers to make sure kids and older adults stay properly hydrated and cool in these hot conditions."

If a person thinks that they, or someone they're with, is experiencing heatstroke they should call 911 or head to the nearest emergency room.