CHICAGO (CBS) — The heavy snow and bitter cold this winter have put a major strain on supplies at Chicagoland blood banks, as donations have dropped precipitously because of cancelled blood drives and missed appointments.

“We’ve never experienced something where both our local supply and our national backup was as constrained as it is right now,” said Lifesource Chief Operating Officer Jim Fitzgerald told WBBM Newsradio’s Lisa Fielding. “We’re at a point right now where we actually need all blood types.”

Nationwide, blood supplies are at critical levels. In Chicago, the month of January already is slower when it comes to blood donations, but with nearly three feet of snow this year, and several days of temperatures below zero, there has been an unprecedented drop in blood supplies.

Lifesource has cancelled 22 blood drives in Chicago this month due to the weather.

“Those 22 blood drives were scheduled to collect more than 1,100 units, which just for the Chicagoland area for us is almost 20 percent of what we would have expected to collect for the entire month,” Fitzgerald said.

It’s not just cancelled blood drives behind the drop in supplies. Just this week, nearly 800 appointments were missed or cancelled due to the extreme cold on Monday and Tuesday, when temperatures were as low as 11 below zero.

“That was a combination of 10 mobile drives that were cancelled over that two-day stretch; donors that had made appointments at donor centers that then called us and said that they were cancelling,” Fitzgerald said.

Fitzgerald said 25 percent of Lifesource donations come from schools, and many have been closed for several days this month due to the weather.

“We count on them to be a big contributor to the blood supply – and so the cancellations have had an impact on us,” Fitzgerald said.

Lifesource has extended its hours, and expanded its mobile blood drive. There are 18 Lifesource locations in Chicago, and they’re encouraging people to donate ahead of another round of bad weather.

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