What is a blood type and how should it be transfused? Why sometimes there are serious complications after a transfusion?

There are four types of blood (blood types) – A, B, AB, and 0. Genes that a person inherits from their parents determine the blood type.

When a blood transfusion is given, it is preferable for patients to receive blood of the same AB0 and RhD group. However, in an emergency or special circumstance, if the same blood group is not available, the patient may be given a different group to which their immune systems will not respond. Blood transfusions do not need to be matched to gender or race.

Blood transfusion from the wrong AB0 group can be life threatening. For example, if someone with type B blood is given a type A blood transfusion, their antibodies will attack the type A cells.

This is why type A blood cannot be transfused to someone who has type B blood and vice versa.

Group 0 red blood cells do not have antigens A or B, so they can be transfused to any other group.