By Suzanne Le Mignot

EVANSTON, Ill. (CBS) — Some hospital emergency rooms were busy Friday as 100-degree temperatures lingered in the Chicago area.

Northwestern Memorial reported three heat-related cases, while North Shore in Evanston had a few patients, including some asthma sufferers feeling the heat.

CBS 2’s Suzanne Le Mignot spent time with patients at another Evanston hospital, St. Francis.

The hospital’s emergency room saw about four heat-related cases per hour.

Dewayne Lucas of Rogers Park was among the people rushed by ambulance to the ER. He said he experienced chest pains after moving from the outside into cooler temperatures.

“It’s like a throbbing pain. I felt like I was having some kind of heart attack. I never experienced it. I was terrified,” Lucas said.

Lucas, who is 37 and in great shape, says he didn’t want to take any chances.

“I was walking for a little while. That’s it. I wasn’t really doing anything strenuous. I really didn’t think about it being heat-related, but that may make sense,” he said. “This was definitely an eye-opener and a warning for me to take this heat more seriously.”

ER physician Scott French says heat can stress a person’s body from head to toe.

“Whether it’s the brain to cause someone to have a stroke or whether it’s the heart, it can affect it in all those ways to really exacerbate the medical problems that they may not even know they have,” he said.

Dr. French says the heat can also have a big impact on those with pre-existing conditions. Sandy Bjornson has diabetes and is on dialysis.

“I couldn’t get up the stairs to my second-floor apartment today, and I called the fire department and they decided they should bring me in,” she said.

Bjornson has this message for anyone who feels the heat may be getting the best of them: “Go someplace where it’s cool — a grocery store, a restaurant, your car if you have air-conditioning. Just stay cool because this heat is killing people.”

You hear it all the time: Drink plenty of water in weather like this. But Dr. French also says drinks that replace electrolytes, like Vitamin Water or Gatorade, are good to drink, too.

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