Blood exchange therapy is used in the treatment of blood, rheumatoid immunity, infection, poisoning and other related diseases, and has certain efficacy in critical and severe refractory related diseases. 1. Blood exchange therapy generally refers to plasma replacement therapy, which is often used clinically for thrombotic thrombocytopenic purpura, neonatal hemolytic disease, systemic lupus erythematosus and other diseases. 2. Generally, by replacing normal blood, autoantibodies are removed from the body in order to achieve the purpose of treating the disease. 3. Blood exchange therapy may have the risk of thromboembolism, allergies, electrolyte disorders, cardiac arrest, infections, and so on. Evaluation of blood transfusion therapy should be based on the needs of the disease and the suitability of blood transfusion therapy should only be considered after evaluation by a professional physician.