the diuretic of choice in treatment of AHTR with decreased urine output, because it increases the amount of blood that reaches the renal cortex. Mannitol may also be used. Dopamine is used for blood pressure support because it causes vasodilation (dilation of blood vessels) in the kidneys as well as increasing the cardiac output (amount of blood pumped by the heart each minute). Prognosis The severity and prognosis of acute hemolytic transfusion depends on the rate of blood administration and the total volume of the transfusion. Approximately 2% of cases are fatal. Reactions that begin sooner are typically more severe. Epidemiology Acute hemolytic transfusion reaction is estimated to occur in 1 in 38,000 to 1 in 70,000 transfusions. An estimated 41% of ABO-incompatible transfusions result in AHTR. References Transfusion reactions Complications of surgical and medical care Transfusion medicine