Blood transfusions are an important part of hematologic care. Transfusion is the transfer of blood, its components, or products from one person (donor) into another person’s bloodstream (recipient). Every year in the U.S., more than 20 million units of red blood cells, platelets, and plasma are transfused to treat hematologic conditions such as severe anemia, leukemia, and sickle cell disease. Transfusions have long been associated with some risk to patients. The HIV epidemic during the 1980s was a major cause of fear; regular transfusions, especially of clotting factor concentrates, spread the virus quickly and nearly undetected. That outbreak prompted the development of biovigilance or hemovigilance: tracing and tracking transfusion-related adverse events and incidents, both infectious and non-infectious, that affect blood donors and recipients. Another of the most significant issues complicating transfusion safety has been bacterial contamination of blood products, particularly of platelets. However, steps have been taken in the last decade to avoid, detect, and eliminate this complication through improved donor selection, specialized preparation of the arm before needle insertion, and special screening techniques.
Despite ongoing improvements in the collection, processing, testing, delivery, and monitoring of transfusions during the past several decades, concerns over the safety of these therapies and the process in general continue today.
Historically, there was concern about transmitting infectious diseases from a donor to a recipient. Now blood is regularly tested for infectious disease transmission, particularly for viruses such as Hepatitis B and C, HIV, and West Nile Virus. Traditionally, serum has been tested to look for the body’s response to past infectious exposure, but many serum tests have been replaced by molecular testing called nucleic acid amplification testing (NAT), which finds active viruses in the donor’s blood to determine infection risk. If an active virus is found, the donor unit is discarded. Experts anticipate that new methods, including new molecular and microarray testing, which can identify many infectious agents rapidly and accurately, will replace or augment serum studies and NAT in the near future. Blood transfusion has never been safer from known infectious risk than it is today.
In addition to infectious disease risks, doctors must also manage other risks, such as post-transfusion reactions. These include transfusion-related lung injury (TRALI), during which the donor’s immune antibodies cause breathing problems in the recipient; transfusion associated cardiac overload (TACO), which is swelling caused by the increased blood volume; and post-transfusion iron overload, which is a buildup of iron in the body, usually caused by multiple or regular transfusions.
In addition to infectious disease risks, doctors must also manage other risks, such as post-transfusion reactions. These include transfusion-related lung injury (TRALI), during which the donor’s immune antibodies cause breathing problems in the recipient; transfusion associated cardiac overload (TACO), which is swelling caused by the increased blood volume; and post-transfusion iron overload, which is a buildup of iron in the body, usually caused by multiple or regular transfusions.
Source :: http://www.hematology.org
This article was published in December 2008 as part of the special ASH anniversary brochure
