Question

Why there is no universal donor anymore? What type of blood you can transfuse if patient has type B+ blood?

Answer 1

O negative blood type used to be considered the universal blood donor type but it's now known that even type O negative blood may have antibodies that can cause serious reactions during a transfusion. There are four types of blood i.e A, B, AB and O depending on the presence of antigen A and B in the blood. Since O negative type neither has A nor B antigen, therefore, its transfusion to any person used to be considered safe as there is no induction of any type of antigen. But compatibility of blood is seen on other parameters along with presence and absence of antigen A and B. Such as, blood is also subdivided into whether it carries a separate antigen rhesus, Rh called the Rh factor. Someone who has the Rh antigen and is blood type B can thus be referred to as type B +, while an otherwise identical person without the Rh antigen would be type B- Ideally, blood transfusions are done with donated blood that's an exact match for type and Rh factor.

A patient with type B+ blood should be transfused the blood which has both the antigens B and Rh.

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