Aging is not bad -- even for blood
Dr KK Aggarwal
The view that “when blood transfusions are needed, it may be best to use the freshest blood” is no more true as per McMaster University researchers.
A study of 31,497 patients published in the New England Journal of Medicine of almost 31,500 patients at six hospitals in four countries (Australia, Canada, Israel and the U.S) has shown that having a transfusion with the freshest blood did not reduce the proportion of patients who died in hospital.
"our study finally puts an end to the question about whether stored blood could be harmful and fresher blood would be better," said Nancy Heddle, lead author and a professor emeritus of medicine for McMaster's Michael G. DeGroote School of Medicine. "Our study provides strong evidence that transfusion of fresh blood does not improve patient outcomes, and this should reassure clinicians that fresher is not better."
Having a supply of stored blood helps to ensure that blood is available when a patient needs it.
The mortality rate was 9.1 per cent with people receiving the freshest blood, and 8.7 per cent among those receiving the oldest blood.
Advances in blood storage now allow blood to be stored up to 42 days before transfusion and the usual practice is to use up the blood that has been in storage the longest. But, because there are biochemical, structural and functional changes in the blood during storage, there had been concerns about the use of 'older' blood. [source science daily]