Any unfavorable and harmful transfusion related events occurring in the patient during or after transfusion of blood or components is called transfusion reaction.
Blood transfusions are one of the most common procedures for patients in the hospital. Transfusion reactions are the most frequent adverse event associated with administration of blood products. Transfusion reactions may be seen in up to 1% of transfusions. Transfusion. reactions can range from mild to life threatening events. Transfusion reactions can rarely be fatal. The incidence of such fatal reactions varies from 1 in 0.6 million to 2.3 million.
A patient suffering from an iron deficiency or anemia, a condition where the body does not have enough red blood cells, may receive a red blood cell transfusion. This type of transfusion increases a patient's hemoglobin and iron levels, while improving the amount of oxygen in the body.
Plasma is the liquid part of the body's blood. It contains important proteins and other substances crucial to one's overall health. Plasma transfusions are used for patients with liver failure, severe infections, and serious burns.
Platelets are a component of blood that stops the body from bleeding. Often patients suffering from leukemia, or other types of cancer, have lower platelet counts as a side effect of their chemotherapy treatments. Patients who have illnesses that prevent the body from making enough platelets have to get regular transfusions to stay healthy.
Immune-mediated transfusion reactions typically occur due to mismatch or incompatibility of the transfused product and the recipient. They include naturally occurring antibodies in the blood recipient (such as anti-A, anti-B which are typically responsible for acute hemolytic transfusion reactions) as well as antibodies made in response to foreign antigens (alloantibodies). These alloantibodies account for many reactions including mild allergic, febrile non-hemolytic, acute hemolytic and anaphylactic. Antibodies present in the blood donor can also cause reactions and are thought to be involved in transfusion- associated lung injury (TRALI).
Non-immunologic reactions are usually caused by the physical effects of blood components or the transmission of disease. Bacterial contamination, for example, results in septic transfusion reactions and is caused by bacterial and/or endotoxin contamination of a blood product. This may happen at the time of collection due to inadequate blood donor arm disinfection, the presence of bacteria in the donor's circulation at the time of collection, or due to improper product handling after collection.
Often patients who have received a blood transfusion experience no complications or problems. However, minor to severe problems do occasionally occur. Some people have allergic reactions to blood received during a transfusion, even when given the right blood type. In these cases symptoms include hives and itching. Like most allergic reactions, this can be treated with antihistamines. However, a doctor should be consulted if the reaction becomes serious.
Transfusion reactions include urticaria, fevers, and hemolysis caused by antibodies in the recipient directed against components of the transfused product, including antigens on the red blood cells (RBCs) themselves, plasma proteins, or antigens on contaminating white blood cells or platelets.
Developing a fever after a transfusion is not serious. A fever is your body's response to the white blood cells in the transfused blood. However, it can be a sign of a serious reaction if the patient is also experiencing nausea or chest pain. Patients should consult their doctors if other symptoms or side effects are present.
Acute reactions occur within 24 hours of transfusion and include acute hemolytic, febrile nonhemolytic, allergic, and transfusion-related acute lung injury (TRALI). Delayed reactions occur days to weeks after the transfusion and include delayed hemolytic transfusion reactions, transfusion-associated graft-versus-host disease, and post-transfusion purpura.
An acute immune hemolytic reaction is a very serious, but rare, reaction caused by a patient's body attacking the transfused red blood cells. The attack triggers a release of a substance that damages the kidneys. This is often the case when the donor blood is not a proper match with the patient's blood type. Symptoms include nausea, fever, chills, chest and lower back pain, and dark urine.
All donated blood is screened and tested for potential viruses, bacteria, and parasites. However, occasionally these agents can still infect a patient after a transfusion. The risk of catching a virus or any other blood-borne infection from a blood transfusion is very low. All donated blood is thoroughly tested for HIV. There is a 1 in 2 million chance that donated blood will not only carry HIV but also infect a transfusion recipient. The odds of catching hepatitis B from donated blood is about 1 in 300,000. The risk with hepatitis C is 1 in 1.5 million. The risk of catching West Nile Virus from a blood transfusion is approximately 1 in 350,000.
Although infrequent, non-immune transfusion reactions, including hemolysis, transfusion-associated sepsis, and circulatory overload, should be considered in the differential diagnosis. Acute hemolytic transfusion reactions are most often the result of error. Identification is critical because of the high probability of a second patient receiving the wrong blood product at the same time.
Treatment depends upon the type of transfusion reaction. Although pretransfusion prophylactic acetaminophen and diphenhydramine are often routinely administered, there is little evidence to support this practice. When a transfusion reaction is suspected, the transfusion should be immediately stopped, and the intravenous line should be kept open using appropriate fluids (usually 0.9% saline). A clerical check should be performed by examining the product bag and confirming the patient’s identification. The patient’s vital signs should be monitored and recorded at 15-minute intervals. A post-transfusion blood sample should be drawn and sent to the lab, in addition to sending the bag and tubing if possible. The blood bank generally completes additional testing and clerical checks to rule out an incompatible transfusion. Treatment of specific transfusion reactions is most often supportive. For example, antihistamines (such as diphenhydramine) can be given for a mild allergic reaction, or an antipyretic can be given for a non-hemolytic febrile transfusion reaction.