What occurs when a B+ patient receives A+ blood?

• A. There is no reaction since B+ blood can accept A+ blood
• B. The recipient's anti-A immunoglobulins attack the A+ blood
• C. The blood transfusion improves oxygen delivery
• D. The B+ patient will have increased blood pressure

Answer: (B)

When a B+ patient receives A+ blood, the correct response involves the immune reaction triggered by the transfusion. In this case, the recipient's immune system has antibodies, specifically anti-A immunoglobulins, that recognize the A antigens present on the A+ red blood cells as foreign. This immune recognition leads to the activation of the recipient's immune response, where these antibodies will bind to the A antigens on the donated red blood cells. This binding marks the A+ blood cells for destruction, which can result in a hemolytic transfusion reaction. The body's defense mechanisms, including complement activation and phagocytosis by immune cells, then cause the destruction of the incompatible A+ blood cells.

This is fundamental in blood transfusion compatibility, as mismatches can lead to severe and potentially life-threatening reactions. Hence, it is crucial for transfusion recipients to only receive blood that matches their blood type to avoid these adverse reactions.