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Study findings indicate a major breakthrough in blood transfusions

Photo: DUP Photos, CC,

A new study by researchers at the University of Ottawa is changing the way doctors look at blood transfusions.

The study compared the recovery rates of two groups of patients, one group given fresh blood and the other given older blood, and found no link between recovery and the age of the blood being transfused.

“Our trial directly tested that hypothesis and found that fresh blood actually wasn’t better for you,” said study leader Dr. Dean Fergusson, director of the Ottawa Hospital Research Institute’s clinical epidemiology program and a medical professor at the U of O.

The scientists’ study compared mortality rates of patients who received older and newer transfusions after 90 days in intensive care. In the 2,430 person study, 423 people who received the fresher blood passed away after 90 days, while 398 people who received older blood died.

The findings are groundbreaking, considering 1 million units of blood are transfused every year in Canada, and 198 million units are transfused worldwide.

Without an expiration date, donated blood won’t have to go to waste.

Blood transfusions typically are used to treat people suffering from heart disease, cancer, or leukemia, or people who are injured in car crashes or other accidents. According to Dr. Fergusson, the average patient who needs a transfusion requires two to three units of blood, with each unit totalling 450 mL of blood.

Many doctors believe fresher blood is more effective than older blood, meaning they would ask for fresher blood believing it would be beneficial to patients. However due to high demand, and limited supply, Canadian blood agencies have to use the oldest blood first to avoid wastage.

Canadian Blood Services currently stores donated blood for up to 42 days before disposing of it. The findings means blood agencies don’t need to worry about supplying fresher blood to patients.

“There was growing pressure on the blood banks and on the blood system,” said Dr. Fergusson, adding that health practitioners in Canada would’ve had to make changes to their system and focus on sending fresher blood to hospitals sooner, if the study had shown more positive results from fresh blood.

Dr. Fergusson’s next project will be to study the effects of different ages of blood transfusions on paediatric patients.