A blood transfusion is a safe, common procedure in which blood is given to you through an intravenous (IV) line in one of your blood vessels. Blood transfusions are done to replace blood lost during surgery or a serious injury. A transfusion also may be done if your body can't make blood properly because of an illness.
During a blood transfusion, a small needle is used to insert an IV line into one of your blood vessels. Through this line, you receive healthy blood. The procedure usually takes 1 to 4 hours, depending on how much blood you need.
Blood transfusions are very common. Each year, almost 5 million Americans need a blood transfusion. Most blood transfusions go well. Mild complications can occur. Very rarely, serious problems develop.