Age of Stored Blood Affects Cardiac Surgery Success

A new study has found that cardiac surgery patients who received transfusions of blood that had been stored for 2 weeks or less had lower rates of complications and death than those who received blood that was older.

Researchers at the Cleveland Clinic Foundation (OH, USA) examined data from 6,002 patients given red blood cell (RBC) transfusions during coronary artery bypass grafting (CABG), heart-valve surgery, or both between June 30, 1998, and January 30, 2006. The researchers compared a total 2,872 cardiac surgery patients who received transfusion blood that had been donated within the previous 2 weeks with 3,130 cardiac surgery patients who received transfusion blood that had been donated more than 2 weeks earlier. Multivariable logistic regression with propensity-score methods was used to examine the effect of the duration of storage on outcomes.

The researchers found that the patients who were given older blood had a higher risk of dying in hospital than their newer blood counterparts were (2.8% versus 1.7%), and significantly more likely to need prolonged ventilation support, experience kidney failure, sepsis, or multiple organ failure. Mortality at one year was significantly less in patients given newer blood (7.4%) compared to those given older blood (11%). The investigators also discovered a direct dose response relationship between days of storage and the chances of a combination of serious complications or adverse events. After eliminating potential confounding factors, an analysis revealed that patients who had received older blood had a significantly higher rate of combined serious adverse events than those who received newer blood. The study was published in the March 20, 2008, issue of the New England Journal of Medicine (NEJM).

"In patients undergoing cardiac surgery, transfusion of red cells that had been stored for more than two weeks was associated with a significantly increased risk of postoperative complications as well as reduced short-term and long-term survival,” concluded lead author Colleen Koch, M.D., M.S., and colleagues of the department of cardiothoracic anesthesia.

Previous studies have already raised questions about the shelf life of donated blood and attendant risks to patients. Some hospitals have brought in new procedures to minimize the use of donated blood during cardiac surgery, such as reducing anemia before surgery, using drugs to stop bleeding during and after surgery, collecting blood lost by the patient during surgery to be reused, and even discharging patients with a lower than normal RBC count.


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Cleveland Clinic Foundation