Platelets in the donor blood also get broken down by the host body, resulting in "purpura," dark purple spots on the skin. The reactions are mild, but doctors don't like to take chances. These days most donor blood is separated into its components before it's deployed.
White blood cells are entirely removed — a process called leukodepletion. The first sign of a transfusion gone wrong is "a feeling of impending doom. Other sign of a mismatched blood type is the usual immune system warning flags — flu-like fever, ache, and chill, as well as a burning sensation at the injection site. If you're lucky, bad fever and chills are the extent of the reaction. Your immune system will break down the foreign red blood cells, but before doing so, the macrophages in your immune system will engulf them.
The red blood cells get filtered out of the blood vessels and broken down in the liver and the spleen. After that there's no more fuss. They're excreted with other waste material.
Things get dangerous when the immune system doesn't wait for the foreign red blood cells to clear the blood vessels before it splits them apart. Hemolysis — the splitting of these cells — spills their contents into the blood vessels.
Patients who require blood products should have a signed informed consent form and a type and screen performed prior to transfusion, whenever possible. If the patient is unstable and requires emergent uncrossmatched blood, a type and screen should still be sent for subsequent transfusions.
If the patient has a previous type and screen on file with the blood bank, it should be the same ABO and Rh type as the current sample; otherwise, the suspicion for a mislabeled blood specimen should be high. Room number should never be used to identify a patient. Prior to administering blood products, two providers usually RNs should confirm the quantity and type of product, the ABO and Rh type, and the serial number of the product.
Many centers have instituted a checklist to ensure compliance with each of these steps. These indicate the types of antigens present on the surface of the RBCs. A second major surface antigen is the Rhesus factor or Rh factor. However, in women of childbearing age, it is a concern because the fetus and mother can have a different Rh status. This process can be prevented by administering rho d immune globulin to the mother when there is a concern or high risk for feto-maternal hemorrhage, even in small quantities.
There are two major categories for blood transfusion reactions: immune-mediated and nonimmune-mediated. Immune-mediated reactions include all cellular and humoral responses to blood products, while nonimmune-mediated reactions include volume overload, electrolyte abnormalities, and hypothermia, among others [ 3 ].
Signs and symptoms include fever, chills, back or flank pain, or changes in vital signs specifically, blood pressure and heart rate. An acute hemolytic reaction is an immune-mediated event, which typically occurs within the first 24 hours of a transfusion [ 4 , 5 ]. It is due to ABO incompatibility and is most commonly due to human error. Antigen-antibody complexes form between donor and patient blood, leading to complement fixation and catastrophic intravascular hemolysis, which in turn can lead to shock, renal failure, and potentially death [ 6 ].
Delayed hemolytic reactions can occur days or even weeks after a blood transfusion and are caused by previously formed antibodies in the patient, which react with antigens on the surface of the donor cells [ 4 , 5 ]. These are not ABO incompatibility reactions but are instead caused by minor antigen incompatibility. These reactions are difficult to diagnose due to their nonspecific symptoms and delayed onset after a transfusion.
They are more common in patients who have undergone multiple transfusions in the past. Febrile nonhemolytic reactions are also immune-mediated but do not result in the destruction of RBCs. A transfusion should be immediately stopped once there is a concern for a febrile reaction, and the remaining blood products and IV tubing should be returned to the blood bank to rule out acute hemolysis or bacterial contamination.
If these tests are negative, a febrile nonhemolytic reaction can be diagnosed. A majority of patients who are diagnosed with this type of reaction will not have subsequent reactions in the future; however, if a second reaction does occur, the patient should then only be given leukocyte-reduced products and may benefit from receiving antipyretics prior to transfusion [ 6 ].
Posttransfusion purpura is an immune-mediated reaction to blood products which results in severe thrombocytopenia. This is a rare disorder caused by alloantibodies against a platelet antigen and is characterized as a precipitous drop in platelets approximately 1 week after blood product administration. Signs and symptoms include purpura, gastrointestinal GI bleeding, gross hematuria, or excessive wound bleeding.
Treatment includes administration of corticosteroids and IV immunoglobulin or plasmapheresis. There are two immune-mediated allergic processes associated with transfusion reactions, which are urticarial and anaphylactic reactions. Urticarial reactions are immunoglobulin E IgE -mediated and consist of GI distress nausea and vomiting, abdominal cramping, and diarrhea and mild upper respiratory symptoms such as rhinorrhea. Treatment consists primarily of antihistamines.
Anaphylactic reactions are IgA mediated and begin within seconds to minutes of the start of transfusion. These reactions occur primarily in patients with selective IgA deficiency but can also occur in patients with antibodies to other donor plasma proteins.
Treatment includes immediately stopping the transfusion, securing the airway including intubation, if needed , and giving epinephrine, corticosteroids, and antihistamines [ 6 ]. Transfusion-associated acute lung injury TRALI is an immune-mediated transfusion reaction, which manifests as an inflammatory lung injury within the first 6 hours of transfusion. It is due to donor granulocyte-induced acute respiratory distress syndrome ARDS.
The chest X-ray findings are the same as in other causes of ARDS, namely, diffuse bilateral pulmonary infiltrates, and the treatment is the same lung protective ventilation strategies and supportive care. Graft-versus-host disease can be seen in severely immunocompromised patients who receive blood products. It is an immune-mediated transfusion reaction caused by donor T lymphocytes, which attack patient human leukocyte antigen HLA antigens.
Signs and symptoms include rash, elevated liver function test LFTs , diarrhea, and bone marrow suppression and typically develop a week or more after transfusion. One blood component that affects the blood's ability to clot is platelets. A reduced number of platelets thrombocytopenia or the failure of platelets to function properly increases the time it takes for bleeding to stop increased bleeding time. Transfusion with platelets improves the clotting time, which reduces the risk of uncontrolled bleeding.
This treatment does not cure the cause of platelet loss. Anemia is a decrease in the number of oxygen-carrying red blood cells or a decrease in the amount of hemoglobin , the oxygen-carrying substance in the red blood cells. There are several types of anemia, each with a different cause, and each is treated differently. Severe anemia may be treated with a transfusion of packed red blood cells. This temporarily increases the number of oxygen-carrying red blood cells in circulation and may improve symptoms, but it does not treat the cause of the anemia.
Almost all of the blood used for blood transfusions is donated by volunteers. For details on the donation process, see Donating Blood. The TPD enforces five layers of overlapping safeguards to protect the blood supply against disease. These safeguards are implemented by Canadian Blood Services, the national organization that collects and distributes blood and blood products in all provinces and territories except Quebec. Your blood is typed, or classified, according to the presence or absence of certain markers antigens found on red blood cells and in the plasma that allow your body to recognize blood as its own.
If another blood type is introduced, your immune system recognizes it as foreign and attacks it, resulting in a transfusion reaction. People with type A have antibodies in the blood against type B.
People with type B have antibodies in the blood against type A. People with AB have no anti-A or anti-B antibodies. People with type O have both anti-A and anti-B antibodies. People with type AB blood are called universal recipients, because they can receive any of the ABO types. People with type O blood are called universal donors, because their blood can be given to people with any of the ABO types. Mismatches with the ABO and Rh blood types are responsible for the most serious, sometimes life-threatening, transfusion reactions.
But these types of reactions are rare. The Rh system classifies blood as Rh-positive or Rh-negative, based on the presence or absence of Rh antibodies in the blood. People with Rh-positive blood can receive Rh-negative blood, but people with Rh-negative blood will have a transfusion reaction if they receive Rh-positive blood. Transfusion reactions caused by mismatched Rh blood types can be serious.
There are over other blood subtypes. Most have little or no effect on blood transfusions, but a few of them may be the main causes of mild transfusion reactions.
Mild transfusion reactions are frightening, but they are rarely life-threatening when treated quickly. The risks of blood transfusions include transfusion reactions immune-related reactions , non-immune reactions, and infections. Immune-related reactions occur when your immune system attacks components of the blood being transfused or when the blood causes an allergic reaction. This is called a transfusion reaction. Even receiving the correct blood type sometimes results in a transfusion reaction.
These reactions may be mild or severe. Most mild reactions are not life-threatening when treated quickly. Even mild reactions, though, can be frightening. Mild allergic reactions may involve itching, hives, wheezing, and fever. Severe reactions may cause anaphylactic shock. Doctors will stop a blood transfusion if they think you are having a reaction. A reaction may turn out to be mild.
But at the beginning, it is hard for doctors to know whether it will be severe. There are several immune-related transfusion reactions. Fluid overload is a common type of non-immune reaction. A person can develop iron overload after having many repeated blood transfusions.
This condition, sometimes called acquired hemochromatosis , is often treated with medicine. Too much iron can have an effect on many organs in the body. The transmission of viral infections, such as hepatitis B or C or HIV , through blood transfusions has become very rare because of the safeguards enforced by Health Canada's Therapeutic Products Directorate TPD on the collection, testing, storage, and use of blood.
The risk of infection from a blood transfusion is higher in less developed countries, where such testing may not happen and paid donors are used. It is possible for blood to be contaminated with bacteria or parasites. Bacterial contamination can happen during or after donation. Donated blood might have a parasitic infection. Transfusion with blood that has bacteria or parasites can result in a systemic infection. But this risk is small. The risk of a bacterial infection in donated blood is small because of the precautions taken in drawing and handling blood.
There is a greater risk of bacterial infection from transfusions with platelets. Unlike most other blood components, platelets are stored at room temperature. If any bacteria are present, they will grow and cause an infection when the platelets are used for transfusion. Before you receive a blood transfusion, your blood is tested to determine your blood type. Blood or blood components that are compatible with your blood type are ordered by the doctor. This blood may be retested in the hospital laboratory to confirm its type.
A sample of your blood is then mixed with a sample of the blood you will receive to check that no problems result, such as red blood cell destruction hemolysis or clotting.
This process of checking blood types and mixing samples of the two blood sources is called typing and crossmatching. Before actually giving you the transfusion, a doctor or nurse will examine the label on the package of blood and compare it to your blood type as listed on your medical record.
Only when all agree that this is the correct blood and that you are the correct recipient will the transfusion begin. Giving you the wrong blood type can result in a mild to serious transfusion reaction. Sometimes a doctor will recommend that you take acetaminophen such as Tylenol , antihistamines such as Benadryl , or other medicines to help prevent mild reactions, like a fever or hives, from a blood transfusion. Your doctor will treat a more severe reaction if one occurs. To receive the transfusion, you will have an intravenous IV catheter inserted into a vein.
A tube connects the catheter to the bag containing the transfusion, which is placed higher than your body. The transfusion then flows slowly into your vein.
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