In major operation, how will you assess the mismatch blood transfusion reaction.
|A||Increase blood pressure|
|B||Increase central venous|
a. The incidence of nonfatal hemolytic transfusion reactions is approximately 1 per 6000 units of blood administered.
b. Fatal hemolytic reactions occur once for every 100,000 units administered. Immediate hemolytic reactions occur during transfusion of mismatched blood (usually ABO mismatch) and are characterized by intravascular destruction of red blood cells and consequent hemoglobinemia and hemoglobinuria
c. Renal toxicity from free hemoglobin in the plasma consists of tubular necrosis and precipitation of hemoglobin within the tubules. Within the circulating blood, DIC can be initiated by antibody–antigen complexes activating factor XII and complement, leading to activation of the coagulation cascade.
e. If the patient is awake, the most common symptoms of immediate transfusion reactions are heat and pain along the vein into which the blood is being transfused, flushing of the face, pain in the lumbar region, and constricting chest pain.
f. In patients who are anesthetized and have an open wound, the two dominant signs are diffuse bleeding and hypotension. There is a sudden fall in the platelet count, an increase in fibrinolytic activity, and consumption of coagulation factors, especially factors V and VIII.
g. The laboratory criteria for a transfusion reaction are hemoglobinuria with a concentration of free hemoglobin over 5 mg/dL, a serum haptoglobin level below 50 mg/dL, and serologic criteria that show incompatibility of the donor and recipient blood. A positive Coombs' test indicates transfused cells coated with patient antibody and is diagnostic.
i. The transfusion should be stopped immediately, and a sample of the recipient's blood should be drawn and sent along with the suspected unit to the blood bank for comparison with the pretransfusion samples.
ii. Because renal toxicity is affected by the rate of urinary excretion and pH, and because alkalinizing the urine prevents precipitation of hemoglobin within the tubules, attempts are made to initiate diuresis and alkalinize the urine. This can be accomplished by mannitol or furosemide plus 45 mEq bicarbonate..