Transfusion Medicine (TM), commonly known as Blood Bank, has undergone a huge advancement in the last few decades. It would be fair to call Transfusion Medicine the backbone of the hospital since it provides support to surgeries, transplants, trauma patients, routine transfusion support in dialysis, chronically transfused cancer patients etc.
Transfusion Medicine has diversified from a laboratory-based approach to a patient-centred clinical speciality. Modern transfusion medicine not only deals with the blood components, its storage & issue, but it has evolved into a multidisciplinary approach encompassing various other specialities & super specialities in terms of life-saving therapeutic procedures.
The clinical TM deals with therapeutic procedures collectively known as “Apheresis”. The term Apheresis means “to take away”. This process uses a centrifuge that separates the blood into its components by density. It is a broad term which is applicable to any procedure that involves removing whole blood from a donor or patient and separating the blood into discrete components so that one specific component can be removed. Therefore, for a donor, it may be used to collect a particular blood component such as WBC, platelets or plasma while for a patient, one or more blood components can be removed to treat a disease.
All apheresis procedures involve directing the blood in the patient/donor's veins through tubing to an Apheresis machine that separates the blood components. The separation is done by either a centrifuge process on the blood in the machine. After the separation, the desired component of the blood is removed, while the rest of the blood components are reinfused back into the patient/donor. The entire procedure is painless which is definitely an added advantage. After removing a blood component, the remaining blood components are then returned to the bloodstream of the patient/donor.
Cellular therapy is a recent field of increasing interest in transfusion medicine. It includes-
Stem cells are immature cells from the bone marrow that can turn into mature red blood cells, white blood cells, or platelets. Two of the most common types of stem cell transplants are autologous and allogeneic transplants.
An Autologous transplant uses a patient’s own stem cells. In this procedure, stem cells are collected from the patient and reinfused into the patient to help produce healthy red and white blood cells and platelets.
An Allogeneic transplant uses stem cells from a donor whose human leukocyte antigens (HLA) match with the patient. Such stem cell donors may be related to the patient, or they may be an unrelated volunteers found through a donor registry (Matched Unrelated Donor). Both kinds of stem cell transplantations are common treatment options for cancers such as leukaemia, lymphoma, multiple myeloma etc.
These patients often require intensive chemotherapy that can destroy their bone marrow and prevent them from creating enough blood cells. Stem cells normally circulate in the blood in very small quantities and can be collected from the blood through a small catheter inserted into a patient/donor’s vein.
The department of TM deals with the collection of these stem cells from the blood using the Apheresis machine. The stem cells thus collected can restore the normal cells of the bone marrow. These cells are collected into a bag and the rest of the blood is returned to the patient/donor.
Today, essentially all stem cell transplants are performed by this method since it is associated with less pain & discomfort to the patient/donor with rapid recovery of blood cell counts in such patients.
Peripheral blood stem cell collection is a safe procedure but just like any other medical/surgical procedure, it is not devoid of side effects. Nevertheless, it is often lifesaving for patients with blood cancer and other serious blood disorders.
This procedure is most commonly used for cancers of the blood system. It can also be used to treat other diseases of the immune system.
Donor apheresis –
The process of apheresis has become essential in providing blood components for therapy. A volunteer donor will undergo apheresis to supply specific components. Donors can give platelet or plasma via this mechanism more often than they can donate whole blood.
In the due course of time, the following procedures will also be started –
Chimeric Antigen Receptor-T cell therapy (CAR T-CELL) - It is a breakthrough in the treatment of cancer where the patient’s own immune cells will be engineered to fight against cancer especially those patients with leukaemia & lymphoma. It is an upcoming technology which has the potential to cure cancer.