Patients with severe anemia require red blood cell transfusion as supportive treatment. If the degree of anemia is not severe, blood transfusion is not necessary. All anemic patients should undergo relevant examinations to determine the cause of the anemia, which can then inform the treatment plan to address the underlying cause. For instance, patients with nutritional anemia need to receive treatment that supplements the materials necessary for blood formation; in cases of anemia caused by malignant hematologic diseases such as leukemia or myeloma, chemotherapy is required to treat the primary disease; for patients with acute hemorrhagic anemia, it is necessary to identify and correct the cause of the blood loss.