Celia Missios knows the importance of blood donations all too well.

In 2006, her life took a traumatic turn when she was struck by a car and left severely injured.

“I started with a C-2 fracture and then multiple broken bones. My diaphragm ruptured, so my liver severed, my lungs collapsed and I was bleeding out,” she said.

It took more than three months before doctors could tell her family that she would live.

Missios credits Canadian Blood Services for keeping her alive.

“I was told that they stopped counting at around 54 units of blood,” she said.

Years later, after a long recovery, Missios has become a regular visitor at the Canadian Blood Services (CBS) clinic at College and Bay streets.

While her need for so many units of blood has left her ineligible to be a donor herself now, she does her part by encouraging others to give blood.

“My attitude has changed a lot because when something like this happens to you, it’s about ‘Do it now.’ That’s not just with blood donations, it’s with everything in life,” she said.

“Don’t put off tomorrow what you might be enjoying today.”

That is the same message Canadian Blood Services is hoping to drive home, as it calls on Canadians to donate what they anticipate will be a critical holiday season.

According to CBS, a string of statutory holidays over December and January has a dire impact on the supply of platelets – “a vital blood component with a seven-day shelf life.”

To combat this, CBS is calling for more than 30,000 blood donors across the country to either book or keep their appointments between Dec. 17 and Jan. 6.

Toronto alone has more than 7,000 open appointments that need to be filled.

The donations will make it possible to upkeep chemotherapy treatments, support trauma victims, cardiac surgeries, and organ transplants, something CBS says often taken place between Christmas Day and New Year’s Day.

“The holiday period is typically a challenging time to collect blood, with many regular donors away or busy with seasonal commitments. But the need for blood does not take a holiday, which is why donations at this time of year are so vitally important for patients,” Rick Prinzen, the chief supply chain officer for Canadian Blood Services wrote in a release on Monday.

“We strongly encourage eligible donors to give blood. Your support will ensure we continue to help every patient, match every need and serve every Canadian.”

To book an appointment or find out more information about blood donation you can visit the Canadian Blood Services website.

With files from CTV News Toronto’s Pauline Chan