With hot and humid summer days comes increased risk of heat illness

Sometimes, summer is quite literally too hot to handle. Despite being preventable, more than 600 people in the United States are killed by extreme heat every year, according to the Centers for Disease Control and Prevention. Brian Babka, MD, a sports medicine physician at Northwestern Medicine Central DuPage and Kishwaukee Hospitals, says heat-related illnesses need immediate recognition and treatment.

"There is likely not a sports medicine physician covering schools, teams, or mass events who has not seen an episode of heat illness," said Babka. "Heat stroke, the most severe heat illness, is responsible for more than 4,000 emergency department visits per year in the United States. More than half of those require hospital admission with a 3.5% fatality rate."

Sweating is the primary way your body cools itself down. It helps your body release heat and reach a cool, healthy temperature. However, sweating is only truly effective when it can evaporate. When it doesn't, your body can overheat, resulting in a heat-related illness.

According to Dr. Babka, heat-related illnesses typically occur with an increased wet globe temperature, a calculation of air temperature and humidity. High humidity makes it harder for sweat to evaporate. No clouds and no wind increases the risk even more.

Common symptoms of heat exhaustion include headaches, dizziness/lightheadedness, fatigue, chills, clammy skin, and possible muscle cramps. Dr. Babka says do not delay treatment. Immediate recognition and treatment will increase the likelihood of preventing heat stroke and possible death.

"Heat exhaustion and heat stroke are very similar on the same heat-related illness spectrum with overlapping symptoms. The diagnosis of heat stroke is defined by the progression of symptoms, altered mental status/confusion, and possibly seizures," said Dr. Babka. "Heat stroke can happen within 15 minutes of being in the heat and is a medical emergency."

Other physical symptoms of heat stroke include a throbbing headache, nausea, shallow breathing, and a rapid and strong pulse. Notably, the absence of sweating is a key sign of heat stroke and the pulse is strong rather than weak like with heat exhaustion.

If you or someone near you is experiencing heat exhaustion, find a cool, preferably air-conditioned space and loosen any tight clothing. Provide water or a drink with electrolytes and apply cool, wet cloths to as much of the body as possible. Fan with a cool mist and elevate lower limbs.

Call 9-1-1 for worsening symptoms, altered mental status/confusion, and increased core temperature.

"If temperature is greater than 104°, use cold water immersion without hesitation," said Dr. Babka. "If not taken seriously, heat-related illness can cause electrolyte abnormalities, muscle cramps, exertional rhabdomyolysis causing kidney failure, and death."

Your ability to tolerate the heat is dependent upon many factors. Age, obesity, fever, dehydration, decreased physical fitness, heart disease, sleep deprivation, mental illness, poor circulation, sunburn, medications and alcohol can all affect whether you stay cool in the hot weather.

When the temperature rises, take precautions:

• Schedule your outdoor time and activities.

• During heat waves, spend as much time in air conditioning as possible.

• Wear lightweight, light-colored clothing.

• Take cool showers.

• Drink more water than usual.

• Don't wait until you're thirsty to rehydrate.

• Always wear sunscreen.

• Pace yourself, slowing down whenever needed.

• Check on your friends, neighbors and those at risk.

• Stay aware of heat advisories.

Dr. Babka encourages athletes to acclimate to heat and humidity over the course of 7 to 14 days. He urges coaches, parents, athletes and medical staff to be properly educated on the signs, symptoms and rapid treatment of heat illness.

"Heat-related illnesses can be difficult to recognize, especially self-recognition due to the associated confusion and altered mental status changes. Many high-level athletes have a psychological drive to complete the planned work out or event and can underestimate the severity of their symptoms," said Dr. Babka. "Actively plan for heat advisories with emergency action plans, and do not be afraid to restrict an event."

To learn more about Northwestern Medicine, visit nm.org.