"Old blood" isn't as safe: should not be stored for more than 28 days?
In earlier entries at this site, we have explained the several problems with the Red Cross blood program and the medical experts' frustration with its' apparent unwillingness to make improvements. Yet another reason for concern over blood safety in the U.S. surfaced this week with the publication of a new study on blood safety. According to Reuters News Agency, patients given blood that is more than 28 days old are twice as likely to acquire a hospital- (or "nosocomial") infection. Sadly, FDA standards allow blood to be stored for 42 days before it must be discarded. The alarming figures come from a study performed at Cooper University Hospital in Camden New Jersey. The researchers looked at the charts of 422 patients hospitalized in ICU over a three-year period. Patients receiving blood stored for more than 28 days, but less than 42 days, were twice as likely to suffer sepsis, pneumonia, urinarty tract infection, heart valve infections and other, similar complications. The researchers noted that the higher rate of infection is caused not by infection existing in the older blood, but rather by degrading of the blood, making the blood and the patient more susceptible to harm. Apparently, over time, stored blood cells release biochemical substances called cytokines that can lower a patient's immune function, rendering them more vulnerable to infection.
Reuters quoted the researchers to the effect that the average age of blood used in U.S. transfusions is 17 days. In March of this year, researchers at the Cleveland Clinic reported that heart surgery patients receivng transfusions of blood more than 14 days old were more prone to complications.