Blood Transfusion: Safer Than Ever
Each year, more than 4 million people need to undergo blood transfusion, reports the American Association of Blood Banks, or AABB. At no time since the first successful blood transfusion was performed in 1795 in the United States has this potentially life-saving procedure been as safe as it is today.
In the nearly three decades since the AIDS virus appeared on the scene, the emergency blood supply in this country has become even safer. This improvement is a result of:
- Better management of the blood-banking process, including donation procedures, patient and blood product identification, blood-preserving techniques, blood storage and blood use
- Advances in blood-testing technology designed to exclude tainted or diseased blood
- Better blood-screening procedures designed to identify donors whose past medical history, travel history, social habits or sexual behaviors increase the chance that their blood could pose a risk to the public's health
But no medical or surgical procedure is fail-safe.
The Risks: Few and Far Between
Despite the many safety measures in place, there are a few risks associated with blood transfusion. Keep in mind, however, that the benefits of this potentially life-saving procedure far outweigh the risks.
The few risks associated with blood transfusions can generally be divided into two broad categories:
In the United States, each unit of donated blood is tested for several different infectious diseases. They include hepatitis C and hepatitis B viruses, human immunodeficiency virus (HIV), human T-cell lymphotropic virus type 1 (HTLV-1) and syphilis.
The risk of contracting any infectious disease from a blood transfusion is extremely small. For example, HIV testing has become so advanced that the risk of transmission of HIV from a blood transfusion in the United States is close to zero.
Very rarely, bacteria can contaminate a bag of red blood cells or platelets. This might occur during collection, processing or storage of the product.
There are some rare cases of other viruses, bacteria and parasites that have been transmitted during a blood transfusion. These are so rare and the tests for them are often so complicated that routine screening is not practical.
Despite the marked reduction in the risk of transfusion-related infectious disease over the past decade, noninfectious reactions continue to be a risk. However, improved administrative techniques have resulted in less frequent severe reactions from transfusions.
Hemolytic transfusion reaction. A hemolytic transfusion reaction — a reaction that destroys red blood cells — is the most common and potentially the most severe reaction associated with transfusion. This occurs when the recipient's plasma and donor's red blood cells are incompatible, causing antibodies in the recipient's plasma to destroy the donor blood.
The U.S. Food and Drug Administration reports that hemolytic transfusion reactions occur twice as often as all infectious blood transfusions. These reactions are responsible for the majority of transfusion-related deaths, estimated to be one in 300,000 to one in 700,000 transfused units.
Hemolytic transfusion reactions are sometimes preventable because they can result from human error at some point in the transfusion process — be it a clerical or administrative error, a mistake in the collection of the blood sample or misidentification of the intended recipient.
Allergic reactions. An allergic reaction may stem from a recipient's sensitivity to allergens in transfused blood plasma. This type of reaction is likely to develop shortly after the transfusion starts. Rarely is an allergic reaction so severe as to pose a risk to the health of the recipient.
Anaphylaxis. Anaphylaxis is a type of severe allergic reaction that occurs very rarely as a result of blood transfusion. The exact cause is not always clear, although it involves a recipient's sensitivity to a donor's blood plasma.
Febrile non-hemolytic transfusion reaction. A febrile non-hemolytic transfusion reaction is characterized by fever and chills. About 1 percent of transfusions of red blood cells and about 10 percent of transfusions with platelets cause fever. This reaction develops after a transfusion is complete or near complete.
Transfusion-related acute lung injury. This condition results in shortness of breath, usually within one to two hours of blood transfusion. Fluid rapidly builds up in the lungs from temporary leakage of fluid out of the tiny blood vessels that line the air sacs. Treatment involves giving the person oxygen and intravenous diuretics. Most people recover within a day or two.