MINNEAPOLIS (WCCO) — Temperatures have dropped below zero the last few days, and hospitals are seeing an uptick in patients with frostbite.

Hennepin Health has treated 29 patients with frostbite since Thursday, and Regions Hospital has treated four. That number will most likely rise with the sub-zero temperatures forecast next week.

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Hundreds of people braved the cold at the Pond Hockey Championships on Lake Nokomis this weekend. Amy Hamilton, who leads the medical team from Tria at the tournament, says the number one thing to do is bundle up.

“I think the most important thing is to make sure that you are wearing layers,” Hamilton said. “Proper layers, and that you are not exposing the skin for too long of a period of time.”

(credit: CBS)

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There are things to look for if you have been outside too long.

“If you start to have that pins-and-needles feeling, starting to go numb, if it starts to get white skin, kind of yellowish or pale, if it starts to get waxy or hard, those are all signs of frostbite and where you want to warm the skin,” Hamilton said.

But even after the skin is warm, there are things to look for.

“If that pins-and-needles feelings doesn’t go back, if the normal sensation doesn’t come back, they don’t feel like they are warming up again, they shouldn’t re-expose and they should make sure they get it checked out,” Hamilton said.

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She says the medical team only treated one minor case of frostbite. They were able to catch it in the early stages, which is crucial.