What happens when two non-compatible blood types are mixed together platelet plug formation vascular spasm coagulation agglutination?

When two non-compatible blood types are mixed together, agglutination occurs. This is the clumping of red blood cells due to the interaction between antibodies in the recipient's plasma and antigens on the donor's red blood cells. This can lead to serious complications, including hemolysis and immune reactions, which disrupt normal blood flow and can damage organs. Other processes like platelet plug formation and coagulation may also be affected, but agglutination is the primary immediate response.