Blood transfusion is a medical treatment to replace blood or portions of the blood lost through injury, surgery, or disease.
During a transfusion, people normally receive only the parts of blood needed to treat their conditions. Whole blood is now rarely given as a transfusion.
Blood for transfusions may come from anonymous donors, or a person could bank his or her own blood in preparation for surgery.
eMedicineHealth Medical Reference from Healthwise
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