Final answer:
The most life-threatening complication associated with blood transfusions is a hemolytic transfusion reaction (HTR), which can lead to organ failure and death. This occurs when a transfusion with an incompatible ABO blood type is given, causing antibodies in the recipient's blood to destroy the donor's red blood cells.
Step-by-step explanation:
The most life-threatening complication associated with blood transfusions is a hemolytic transfusion reaction (HTR). This is a type II hypersensitivity cytotoxic response that occurs when a transfusion with an incompatible ABO blood type is given. In this reaction, antibodies in the recipient's blood bind to and destroy the donor's red blood cells, leading to the release of hemoglobin into the bloodstream. This can cause a range of symptoms including fever, jaundice, hypotension, and disseminated intravascular coagulation. In severe cases, HTR can result in organ failure and death.