Transfusion medicine is the name given to a branch of medicine concerned with the collection and supply of blood reserves and the maintenance of blood banks. After completing regular medical studies and a five-year period of continuing education, a medical professional is entitled to use the professional title of specialist in transfusion medicine.
What is transfusion medicine?
Transfusion medicine deals with the collection and supply of blood in blood banks. With its broadly based, interdisciplinary field of activity, modern transfusion medicine ensures a low-risk and patient-oriented supply of blood units in collaboration with almost all medical specialties. In Germany, many hospitals have specialized in this branch of medicine. They are called institutes for transfusion medicine and transplantation immunology. These institutes not only provide conventional blood products, but also special cell therapeutics. In addition to a large blood bank, they have an affiliated immune hemaglobin laboratory, an HLA and platelet laboratory in the field of transplantation immunology, and a stem cell laboratory. The transfusion physicians are also involved in postoperative patient care. Other subfields include research and teaching.
Treatments and therapies
This medical specialty includes the performance of blood donation and the subsequent production of blood reserves, therapy with blood components and plasma derivatives, and the targeted collection of blood components for therapeutic purposes. Transfusion medicine is used whenever patients suffer from acute blood loss. The body is not able to compensate for this blood loss in a natural way in order to regenerate sufficient blood or individual blood components. Typical areas of application are emergency medicine and operations involving high blood loss, such as organ transplants. Diseases of the hematopoietic system such as leukemia, blood coagulation disorders and anemia are treated in this medical specialty. Blood units are also used in various cancer therapies. Newborns or unborn babies in the womb require a blood transfusion due to anemia caused by rhesus incompatibility. However, transfusion medicine is also used for diseases that are not immediately associated with this specialty: cardiovascular problems, gastrointestinal diseases, and diseases of the nervous system, muscles, skin, hematopoietic organs, connective tissue, and respiratory tract. The German Red Cross provides transfusion physicians with 10,400 units of blood daily. Blood transfusion is performed through a catheter placed before the procedure or through a hollow needle inserted into the vein. It is also possible to donate one’s own blood (autologous blood transfusion). In this case, the donor and recipient are identical. The patient has up to 900 milliliters of blood drawn in one to three sessions four weeks before a planned operation, during which there is a 10 percent probability of high blood loss. During the surgical procedure, the patient receives his or her own blood donation. Thanks to the guidelines on “Preparation and administration of foreign blood products” and high legal requirements, transfusion medicine is very safe nowadays. Only the risk of intolerance reaction and slight side effects remain. A blood or stem cell transfusion can trigger immunologically related complications in the recipient. The patient’s blood system reacts to the foreign substances in the donor blood or stem cells. Different blood groups of donor and recipient can trigger severe immune reactions such as cardiovascular disorders or anaphylactic shock. In rare cases, kidney failure can occur. If the blood types of donor and recipient match, minor, short-term side effects such as chills, fever, drop in blood pressure or nausea may occur.
Diagnosis and examination methods
Because of strict regulatory requirements, nonimmunologic complications are virtually eliminated in transfusion medicine.This risk area includes the transmission of pathogens such as HIV as well as hepatitis B or C.
Pulmonary edema or cardiac insufficiency can occur if large quantities of blood are transfused too quickly. State-of-the-art technology characterizes the laboratories in the specialized clinics and special institutes that ensure the provision of blood reserves. Only when the donated blood preparations are free of pathogens are they released for blood donation. In order for transfusion medicine to guarantee the safety of recipients, it is not only necessary to have state-of-the-art technology, but also to carefully select blood or stem cell donors. Strict guidelines issued by the German Medical Association determine who is eligible as a donor and who is not. Blood donations are separated into their three components: red blood cells (erythrocytes), platelets (thrombocytes) and blood plasma. While the red blood cells ensure the oxygen supply, the platelets are crucially involved in blood clotting. The plasma is the blood fluid. Whole blood donation is no longer common. Legal regulations prohibit the mixing of different blood donations, as this is the only way to ensure that each individual blood unit can be traced back to the donor. The blood concentrates are stored in so-called blood banks. Specialized clinics for transfusion medicine maintain extensive in-house blood banks, while hospitals maintain blood banks with low capacity to cover their own needs. Transfusion physicians must plan the demand for blood reserves precisely, because erythrocyte concentrates have a shelf life of only 42 days, while thrombocytes may no longer be used after just four days. Only blood plasma can be kept frozen for two years. This ensures that the recipient only receives the blood components that he or she really needs during a blood transfusion. Once it has been established that a patient needs a blood transfusion, the transfusion physician conducts a detailed discussion with the person concerned and obtains his or her consent. Only in an emergency will a patient receive a blood transfusion without his or her consent, for example, if there is an acute danger to life after an accident involving high blood loss. The attending physician ensures that the patient receives the appropriate transfusion preparation. A blood group determination and a compatibility test in the form of a crossmatch ensure that donor and recipient are a good match. A small amount of the patient’s plasma is mixed in the laboratory with red blood cells from the donor’s designated concentrate (blood bag). The blood bags contain tubing segments with small amounts of the donor blood to perform the crossmatch. Immediately prior to the blood transfusion, a repeat compatibility check is performed by the so-called bedside test to eliminate any remaining risks such as mix-ups.