DENVER (CBS4) – A lot of people were out and about in Sunday’s cold weather, and as they prepare for a sub-zero drop on Tuesday, doctors are putting out a warning.

University of Colorado Hospital officials say every year around this time they see a surge in frostbite cases. That’s why doctors say it’s important to know how to prevent it, and what to do if it happens.

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Since last January the CU Hospital’s burn center has admitted 18 patients for severe frostbite. The number doesn’t include any minor cases that might have been treated and released in the emergency department or primary care locations.

Robert Strong, who is homeless, knows what it’s like to be cold.

“I’ve lived out on the streets for the last 15 years,” Strong said.

He spent Saturday night at Sloan’s Lake Park.

“As you stay covered inside your sleeping bag, your breathing keeps you warm,” Strong said. “That’s why I was able to survive last night.”

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But it’s not just the homeless who suffer from the frigid winter air. Justin Schoenborn was out for a walk with his dogs on Sunday wearing only shorts.

“I just came from the gym and my legs don’t get cold too easy, so I just figured that I would cover up the top half and put a hat on and I’d probably be good,” Schoenborn said.

But not so fast, according to Dr. Chris McStay, who is Chief of Clinical Operations for the emergency room at CU Hospital. He says skin exposed to the cold doesn’t take long to suffer damage, especially when it’s windy.

Dr. Chris McStay (credit: CBS)

Dr. Chris McStay (credit: CBS)

“People forget when you’re outside and it’s very, very windy; that wind velocity also increases the chance of getting your skin very cold and actually causing frostbite,” McStay said. “Usually put a layer or two on underneath, and put on a warm jacket. Maybe even a top layer above that and make sure my hands and ears are covered.”

If those precautions fail and somebody believes they may have suffered frostbite, doctors say it’s critical to seek emergency care right away. Doctors can administer a specialized medicine to help prevent long-term damage from frostbite so that it doesn’t lead to an amputation.

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