New medical statistics show that the number of infections post-transfusion patients develop after receiving new blood is constantly rising, directly proportional to the "age" of the blood. Packets containing blood that was more than 30 days old were associated with significantly increased risks of developing complications such as nosocomial infections (NOSO) or even death.
 

When in storage, red blood cells give off some biochemical substances, known as cytokines, which play an important role in suppressing the immune system of the patient receiving the transfusion. This can have the worst effects on the receiver, as blood is usually needed when the patient lacks his/her own, so it's very important that the new blood doesn't harm the body even further. Studies have shown that the release of the dangerous cytokines begins at about day 14 and reaches its maximum potential at day 42, when all unused blood must be discarded.
 

Some 422 patients were members in a study, conducted by Cooper University Hospital, aimed at revealing the exact effects that packed red cells have on the receiver's body after the transfusion. During the test, 70 percent of the blood used was more than 21 days old. Out of the recipients, more than 11 percent died, 32 people developed one NOSO, 21 exhibited signs of 2 NOSO and 4 had 3 NOSO infections.
 

Among the test subjects, patients who received blood older than 29 days were twice most likely to develop nosocomial infections than people who received blood that was only a few days old. This new research shows that the current hospital policies, of using older blood samples first, so that they don't go to waste, is very wrong. Patients should always receive the freshest blood available.
 

The president of the American College of Chest Physicians, James A. L. Mathers, Jr., MD, FCCP, said "The results of this study raise questions about current blood storage standards and transfusion practices and suggest additional research is needed in these areas."