Blood's Shelf Life May Be as Short as 3 Weeks

A small study of how blood ages in storage, and after being transfused in patients who underwent spinal fusion surgery suggests a worrisome finding for the world's blood banking industry, hospitals and transfused patients:  Blood stored longer than 21 days appears to stiffen, making it less able to squeeze into small capillaries and organs that need it.

Current day practice allows the use of blood up to six weeks after it is collected but if the current study's findings hold up in larger studies now underway, blood banks throughout the country would have to consider throwing out blood older than 21 days and shortening its shelf life.

"They'll lose a huge portion of their blood inventory," says Steven M. Frank, MD, the study's author and associate professor of anesthesiology and critical care medicine at Johns Hopkins University School of Medicine.

"This is one more piece to the puzzle suggesting that older, stored red blood cells are not as functional as fresher ones,"  he says, and it's making blood banking organizations like the Red Cross "really nervous."

The study by Frank and colleagues at Johns Hopkins is published in Anesthesia & Analgesia, the journal of the International Anesthesia Research Society.