Old blood or new? New technique can tell

Transfused blood which is older than 14 days produce serious side effects.

London: Old blood used in transfusions can have serious side effects. But now a technique can tell the difference between new and old red blood cells, providing an effective way to monitor the quality of blood supplies.

Even with preservatives, blood stored in banks continues to age, resulting in biomaterials leaking from the red blood cells (RBCs) and subsequent changes to cell properties and function.

Currently, blood stored in a special medium can be used for clinical transfusion for up to 42 days, but monitoring of the blood varies, reports the Journal of Cellular and Molecular Medicine.

Jay Mehrishi, University of Cambridge haematologist and study co-author, said: "Recent trials on cardiac surgery patients involving over 40,000 patients showed that transfused blood which was older than 14 days produced serious side effects.

"The side effects of transfusing old blood are thought to result in acute lung injury and possible adverse effects of the immune system," according to a Cambridge statement.

"In severe trauma patients, transfusion of blood stored for more than 28 days doubled the incidence of deep vein thrombosis and increased death secondary to multiple organ failure.

"Our research will hopefully highlight the significant differences between old and new blood used in transfusions as well as the possibility of using our technique to quickly and cheaply monitor blood supply quality."

"We need simple, routine quality control monitoring of blood in storage to avoid the serious adverse effects caused by biomaterials released from damaged cells accumulating," said Mehrishi.

Mehrishi believes the technique could also be used to ensure a high quality of `cleaned up` blood which is of immense practical clinical importance worldwide.