White blood cells in the blood contain HLA antigens, and plasma contains plasma proteins, which are the main cause of allergic reactions and febrile reactions. For patients who require multiple infusions of red blood cells, infusion of washed red blood cells can effectively reduce the incidence of these reactions. Washing red blood cells, that is, whole blood, after centrifugation, first separate the plasma and remove the white blood cells under aseptic conditions, add the sterile physiological saline to the red blood cells, and then centrifuge to remove the residual white blood cells, and then repeatedly wash 3 times to finally remove 98% or more. The plasma, more than 90% of white blood cells and platelets, also removes metabolites such as potassium, ammonia and lactic acid produced during the preservation process, retaining more than 70% of red blood cells, and finally suspending physiological saline.
Washing red blood cells are suitable for: (1) Patients who develop allergic reactions (such as measles, angioedema, anaphylactic shock, etc.) after entering whole blood or plasma. (2) Patients with autoimmune hemolytic anemia and paroxysmal nocturnal hemoglobinuria who require blood transfusion. (3) Patients with hyperkalemia and liver and kidney dysfunction requiring blood transfusion. (4) Patients who have caused transfusion and fever due to white blood cell or platelet antibodies due to repeated blood transfusions.