Question

what are ABO and Rh blood system? What is a blood transfusion? What is blood typing? And What is crossmatch? Why blood typing and crossmatch is important before a patient receiving blood transfusion?

Answer 1

ABO blood system, discovered by Karl Landsteiner, classifies human blood group into four different types, based on the type of glycoproteins present on the surface of red blood cells. The four types of blood group according to ABO system are- A, B, AB and O. Rh blood system is another blood grouping system, which classifies human blood based on the presence or absence of Rh (Rhesus) factor. Rh negative blood means that the Rh factor (D antigen) is absent, while presence of Rh factor (D antigen) makes the blood Rh positive. Both of these blood grouping system is extremely important during blood transfusion.

Blood transfusion is a process, when blood, taken from a healthy donor, is transferred or transfused into a compatible recipient. It is mainly done when the recipient is suffering from blood related disorders, such as hemophilia, or in case of any accident, where the patient has lost too much blood, etc.

Blood typing is a process, which determines the type of blood, a person has, based on the proteins present on the surface of red blood cells. It plays an important role in determining whether blood transfusion should be done or not. Only when the blood type of donor and recipient matches, blood transfusion can be done. Crossmatching is a process which determines what type of reaction will take place, when donor and recipient blood is mixed. This indicates, whether the donor's blood is compatible with the recipient's blood (that is, whether the recipient's body will accept the donor's blood).

Before carrying out blood transfusion, it is extremely important to determine the type of blood present in the recipient and the donor and what reactions will take place when donor's blood is introduced into recipient's body. If the blood types are incompatible, it will result in harmful immune reaction within the recipient's body. For example, type A blood group carries antibody against type B blood group. Therefore, if type B blood is transfused into a patient having type A blood group, incompatibility reactions will occur and in severe cases, will result in death.