Blood Supply
Transfusion-Associated Risks Gao ID: PEMD-97-2 February 25, 1997The U.S. blood supply is safer today than at any time in recent history, with risks from blood transfusions quite small compared with the benefits of transfusion in saving lives. Improved donor screening and education have removed from the donor many persons who are at high risk for disease, and tests used to screen blood for viruses are considerably more sensitive than earlier versions. However, risks remain. Eight of every 10,000 donated units of blood carry a serious risk to the recipient, including allergic reactions, bacteria, reactions to incompatible blood transfusions, and viruses. GAO estimates that four out of 1,000 patients who receive the average transfusion of five units of blood are at risk of being exposed to contaminated blood that could sicken or even kill them. On the other hand, as many as half of the 1,000 recipients would be at serious risk of dying immediately unless they receive a transfusion. The risk that a surgery patient will require blood and develop a chronic disease or die as a result of that blood is estimated at five in 100,000. For the average person with no foreseeable plans for surgery, the annual risk of developing a chronic disease or dying from the transfusion is five in 1 million.
GAO found that: (1) the blood supply is safer today than any time in recent history; (2) improved donor screening and education have removed from the donor pool many persons who are at high risk for disease; (2) tests used to screen blood for viruses are considerably more sensitive than previous versions; (3) repeat donors constitute most of the donor pool, which means that they have been tested for viruses on earlier donations; (4) thus, the window of opportunity for infection is considerably smaller than for first-time donors who have never been tested; (5) viral inactivation techniques for plasma derivatives eliminate most viruses that may escape detection on testing and changes in transfusion practices have eliminated some of the circumstances that may have led to unnecessary transfusions in the past; (6) because blood is a biological product, some risk remains; (7) eight of every 10,000 donated units of blood carry some kind of potentially serious risk to the recipient, including allergic reactions, bacteria, reactions to incompatible blood transfusions, and viruses; (8) while these risks may appear to be substantial when considered outside a medical context, it is commonly understood that transfusion provides substantial benefits; (9) GAO reasoned that as many as 50 percent, or 500, of the 1,000 recipients would be at serious risk of dying immediately if they did not receive transfusions; (10) not all recipients of a contaminated unit acquire the disease it contains; (11) many recipients die soon after transfusion from the underlying condition for which the blood was prescribed; (12) the likelihood that a patient will develop chronic disease or die is small for some diseases; (13) GAO determined that the overall risk of developing chronic disease or dying as a direct result of a blood transfusion is about 4 in 10,000; (14) the risk that a general surgery patient will require blood and develop a chronic disease or die as a result of that blood is 5 in 100,000; (15) for the average person in the United States who has no foreseeable plans for surgery, the annual risk of developing a need for surgery, requiring blood, and developing a chronic disease or dying from the transfusion is 5 in 1 million; (16) the risks from transfusing blood to recipients in general and surgery patients specifically are considerably smaller than other hospital-related risks; (17) GAO took a worst case approach to its analysis; and (18) consequently, the actual risks of transfusion may be somewhat lower, but are not likely to be higher than the risks GAO presents.