Blood transfusion

A blood transfusion is a routine medical procedure in which donated blood is provided to you through a narrow tube placed within a vein in your arm. This potentially life-saving procedure can help replace blood lost due to surgery or injury. A blood transfusion also can help if an illness prevents your body from making blood or some of your blood's components correctly.

People receive blood transfusions for many reasons — such as surgery, injury, disease and bleeding disorders. Blood has several components, including: Red cells carry oxygen and help remove waste products White cells help your body fight infections Plasma is the liquid part of your blood Platelets help your blood clot properly A transfusion provides the part or parts of blood you need, with red blood cells being the most commonly transfused. You can also receive whole blood, which contains all the parts, but whole blood transfusions aren't common. Researchers are working on developing artificial blood. So far, no good replacement for human blood is available.

Blood transfusions are generally considered safe, but there is some risk of complications. Mild complications and rarely severe ones can occur during the transfusion or several days or more after. More common reactions include allergic reactions, which might cause hives and itching, and fever.

Your blood will be tested before a transfusion to determine whether your blood type is A, B, AB or O and whether your blood is Rh positive or Rh negative. The donated blood used for your transfusion must be compatible with your blood type. Tell your health care provider if you've had a reaction to a blood transfusion in the past.

Blood transfusions are usually done in a hospital, an outpatient clinic or a doctor's office. The procedure typically takes one to four hours, depending on which parts of the blood you receive and how much blood you need.