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Blood Transfusions

What is a blood transfusion?

A blood transfusion is a procedure in which you receive blood or blood components intravenously. The blood may be from a donor, or, you may receive your own blood that has been stored for you. There are several components of the blood that can be transfused into an adult. Red blood cells are the most common type of blood product transfusion.

There are many reasons you may need a transfusion. Your health care provider will explain the reasons for your transfusion.

Why might I need a blood transfusion?

There are several reasons why you may need a blood transfusion such as:

  • A sudden loss of blood because of an accident or injury
  • Blood loss as a result of surgery
  • A low hemoglobin before, during, or after surgery (hemoglobin is the protein in red blood cells that carries oxygen)
  • Severe heart, lung, liver, or kidney disease
  • Bone marrow failure
  • Moderate to severe anemia (decreased red blood cells)

Human blood is made of a fluid called plasma. Plasma carries red and white blood cells and platelets. Each part of blood has a special function. The components can be separated from each other. Bone marrow, the soft, spongy material in the center of the bones, produces most of the body's blood cells.

Red blood cells carry oxygen from the lungs to other body organs and carry carbon dioxide back to the lungs to be exhaled. A certain number of these cells are needed for the body to function. Bleeding due to injury, surgery, or disease may cause a low red blood cell count.



Plasma carries the blood cells throughout the body. It contains proteins, vitamins, and minerals. Some of the proteins also help the blood to clot. Plasma or fresh frozen plasma can be transfused in people who have a severe deficiency of certain clotting components of the blood.

What are the risks of a blood transfusion?

What are the risks of a blood transfusion?

The blood used at most hospitals is from volunteer donors. Donors are not paid for giving blood or blood products. Each blood donor must answer medical history questions and be given a limited physical exam before being accepted as a donor. The donated blood is carefully tested for:

  • Hepatitis viruses B and C
  • HIV
  • Human T-lymphotropic viruses (HTLV) I and II
  • Syphilis
  • Chagas disease
  • West Nile virus.

These tests decrease the chances of transfusion-related infections.

A directed (or designated) blood donation is one in which donated blood is reserved for a specific person. However, it's recommended that families donate in a particular person's name versus directed donation. This is because unused directed blood is thrown away. If blood is donated in a person’s name, it must be donated within a month of the surgery. If not used, it will be released and used for someone else. An autologous donation is blood you give to be transfused back into your own body if needed for a later, planned surgery.


Serious side effects are rare and may include difficulty breathing, chest pain, and sudden drops in blood pressure. Transfusion reactions can occur even if the donated blood is the correct blood type. Transfusion with blood of the wrong type can be fatal. But this is unlikely to occur because medical personnel check blood multiple times.

How do I get ready for a blood transfusion?

No special preparation is required prior to a blood transfusion.

What happens during a blood transfusion?

A blood transfusion may occur as part of your hospitalization, or it may be done as an outpatient.

  • The blood will be given through a needle or catheter placed in the vein.
  • It may take a few hours to complete the process.

What happens after a blood transfusion?

  • After you have received the blood as requested by your health care provider, the IV that was placed in your arm will be removed and you will be discharged.
  • You will be able to resume your normal activities, unless your health care provider has made other recommendations.

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