When a person with O blood type receives B blood, their anti-B antibodies attack the B antigens on the RBCs leading to agglutination and potentially severe complications. Blood types must be carefully matched to prevent such reactions, with O negative blood being a universal donor used in emergencies.
When a person with O blood type receives a transfusion of B blood, a transfusion reaction is likely to occur. This is because individuals with type O blood produce both anti-A and anti-B antibodies. These antibodies will recognize and attack the B antigens present on the donated red blood cells (RBCs). The response leads to the agglutination (clumping) of RBCs, which can cause blockages in blood vessels and might result in severe medical complications, such as kidney failure, shock, and potentially death.
ABO Transfusion Protocols
To prevent such transfusion reactions, it is essential to match the blood types correctly. The ABO blood group system and the presence of Rh factors play a critical role in determining compatibility for blood transfusions. If emergency situations arise where no time for cross matching is available, type O negative blood, known as the universal donor, is generally used since it does not have A, B, or Rh antigens. Nevertheless, introducing blood from a type O donor into a recipient with a different blood type can still introduce anti-A and anti-B antibodies, but due to the lower volume of transfused blood, the effects are usually limited. Cross-matching before transfusion is always preferable to avoid the risks associated with unmatched transfusions.