SAN ANTONIO -

January is National Blood Donor Month.

The event takes place during a critical time of year, when blood donations are at their lowest.

As a Level 1 trauma center for 22 counties, University Hospital deals with critical cases on a daily basis that require blood transfusions.

"We need blood on the shelf for that that transplant patient getting that call tonight, that individual who has a problem in surgery. You need blood on the shelf today," said Dr. Geralyn Meny, a University Hospital pathologist.

Meny said if there's no blood on the shelf, it could make the difference between life and death, and during the month of January, supplies can get dangerously low.

"It tends to happen this time of year when we're busy with the holidays and the cold weather keeps everyone away," said Meny.

As a nurse, Sari Nesbit said she sees the need firsthand so she makes it a point to donate blood every four to six weeks.

"It's probably one of the best gifts that you can give for free," said Nesbit.

Meny said it can take anywhere from a few minutes to about an hour to make a blood donation, depending on the type of donation.

"It's really not a huge sacrifice at all," said Nesbitt, "and it really doesn't hurt. A lot of people are afraid that maybe it hurts the whole time but it doesn't."   

Experts said just one donation can help save up to three lives.

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