Long-term blood transfusion complications are as follows: 1, a large number of blood transfusion can make circulatory overload, so patients with normal blood volume, transfusion volume is too large or too fast can occur in acute lung injury; 2, due to the process of blood damage there will be lactic acid, potassium, sodium, ammonia and other components increase, the more the patient’s metabolic burden is heavier; 3, blood transfusion will produce homozygous immunity, adverse reactions, because the human blood type system is very complex, homozygous heterozygous blood transfusion will be Because the human blood type system is very complex, isotype transfusion will input a large number of antigens into the recipient’s body and produce corresponding antibodies, resulting in adverse reactions or ineffective transfusion; 4, fever or allergic reaction occurs due to the incompatibility of leukocyte and platelet antigens; 5, there are other adverse reactions to long-term transfusion, and the most common is iron overload caused by iron deposition, leading to abnormal organ function, elevated blood glucose and other hemochromatosis, which needs to be combined with the de-ferritorialization drug treatment.