Although stored red blood cells (RBC) undergo many physiological and morphological changes, results from at least two randomized trials have not found any adverse effects for patients over the short-term.
New results from approximately 47,000 cardiac surgery patients in Sweden observed over a 16 year period found no difference in long-term survival of patients transfused with older RBC. Patients transfused with blood less than 14 days old had similar 30-day, 2-year and 10-year survival as patients transfused with blood stored for 14-27 days or 28-42 days. Furthermore, risk of serious complications was similar in all groups. These results confirm the safety of older RBC and current blood storage policies.
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