A new study has issued a warning regarding blood transfusions, saying that the use of blood for the process could be dangerous. For the study, a group of 60 healthy volunteers were
randomly assigned to receive a unit of red blood cells that had been stored for a duration between one to six weeks. The volunteers were then monitored for 20 hours after transfusion. Within hours after transfusion, seven of the nine volunteers who received the six-week-old blood could not appropriately metabolise the damaged cells, thereby releasing large amounts of iron into their bloodstream. Only one volunteer who received younger blood had a similar response, with blood had been stored for five weeks. None of the volunteers were harmed by the transfusion, but previous studies have shown that excess iron can enhance blood clots and promote infections, the researchers at Columbia University Medical Centre (CUMC) in the US said. “Our recommendation will be controversial, but we think we have real data to support it,” said Steven Spitalnik from CUMC. “Recent studies have concluded that transfusing old blood has no impact on patient outcomes, but those studies did not exclusively examine the oldest blood available for transfusions,” said Spitalnik. Our new study found a real problem when transfusing blood that is older than five weeks,” Spitalnik added. Transfusion of red blood cells is the most common procedure performed in hospitalised patients, with about five million patients receiving red blood cell transfusions annually in the US. “However the longer you store blood, the more the cells become damaged,” said Eldad Hod, associate professor at CUMC. Currently, the US Food and Drug Administration (FDA) allows units of red blood cells to be stored for up to six weeks before they must be discarded. None of the volunteers were harmed by the transfusion, but previous studies have shown that excess iron can enhance blood clots and promote infections.