Using blood that has been stored for more than a period of two weeks may prove fatal for heart surgery patients, finds a new major study.
The research was conducted by doctors at the Cleveland Clinic in Ohio, who found that transfusions with blood stored for more than two weeks were could raise the death risk for patients by nearly 66percent.
The researchers came up with their findings after surveying more than 9,000 heart patients.
Lead researcher Colleen Koch said that recipients of older blood are more at risk from blood poisoning and organ failure.
She told the New Scientist that the study showed the need for stored blood to be classified as outdated earlier than what is the current norm.
"Blood should be classified as outdated earlier than current recommendations," New Scientist quoted her, as saying.
Koch says that the reason blooded stored for more than two weeks may prove to be fatal is because at this stage, stored red blood cells begin to break down, making them more likely to block blood vessels while reducing their capacity to carry oxygen.
"This research suggests that the longer transfused blood has been stored, the greater the risk of complications following cardiac surgery," says Peter Weissberg of the UK charity, the British Heart Foundation.
He added: "Together, these studies suggest that only those heart patients whose lives are at serious risk without a transfusion should receive blood."
"Further research is urgently needed to clarify the indications for transfusion and the effects of blood storage on outcome."