How dangerous is it to get a blood transfusion?

There is some risk.: Blood transfusions have their dangers and risks like anything else. There is a risk of an antibody reaction with an antibody like anti-kidd that was not present in the screening crossmatch, just as there can be a febrile reaction in even a perfect transfusion. However, it is done for a reason, like uncontrolled bleeding, or surgery, and the results of not doing it can be worse. It is therapy.

65 death in 2012: Acute reactions include: hemolytic;febrile, non-hemolytic;bacterial contamination;allergic / anaphylaxis; ransfusion-related acute lung injury (trali) transfusion-associated circulatory overload (taco) chronic reactions include: hemolytic; transfusion associated graft vs. Host disease (ta-gvhd);platelet refractoriness;post transfusion purpura;infectious disease;iron overload.