A blood transfusion is a routine medical procedure that can be lifesaving. During a blood transfusion, donated blood is added to your own blood. A blood transfusion may also be done to supplement various components of your blood with donated blood products. In some cases, a blood transfusion is done with blood that you've donated ahead of time before you undergo elective surgery.

During a typical blood transfusion, certain parts of blood are delivered through an intravenous (IV) line that's placed in one of the veins in your arm. A blood transfusion usually takes one to four hours, though in an emergency it can be done much faster.

A blood transfusion boosts blood levels that are low, either because your body isn't making enough or you've lost blood owing to surgery, injury or disease.

People receive blood transfusions for many reasons, including surgery, injury, bleeding and disease. Blood has several components, including red cells, white cells, plasma and platelets. You'll receive a transfusion that provides the part or parts of blood that will be most helpful for you. Whole blood means the blood contains all its parts. But it is not common to use whole blood for a transfusion.

Researchers are working on ways to develop an artificial blood. So far, no good replacement for human blood is available.

Surgery, injury or anemia

If you lose blood due to surgery or injury, you may experience anemia. You may require a transfusion of packed red blood cells, which means the blood you receive contains a concentration of mostly red blood cells. This type of transfusion is also done for people who have anemia related to other conditions.

Gastrointestinal bleeding

Bleeding from ulcers, enlarged veins (varices) or other conditions of the digestive tract can be life-threatening. Blood transfusions can be lifesaving.

Cancer

Cancer may decrease your body's production of red blood cells, white blood cells and platelets by impacting the organs that influence blood count, such as the kidneys, bone marrow and the spleen. Radiation and chemotherapy drugs also can decrease components of the blood. Blood transfusions may be used to counter such effects.

Other illness

Some illnesses cause your body to make too few platelets or clotting factors. You may need transfusions of just those blood components to make up for low levels.

Infection, liver failure or severe burns

If you experience an infection, liver failure or severe burns, you may need a transfusion of plasma. Plasma is the liquid part of blood.

Blood disorders

People with blood diseases may receive transfusions of red blood cells, platelets or clotting factors.

Severe liver malfunction

If you have severe liver problems, you may receive a transfusion of albumin, a blood protein.

Blood transfusions are generally considered to be safe. But they do carry some risk of complications. Complications may happen during the transfusion or not for weeks, months or even years afterward. They include the following:

Allergic reaction and hives

If you have an allergic reaction to the transfusion, you may experience hives and itching during the procedure or very soon after. This type of reaction is usually treated with antihistamines. Rarely, a more serious allergic reaction causes difficulty breathing, low blood pressure and nausea.

Fever

If you quickly develop a fever during the transfusion, you may be having a febrile transfusion reaction. Your doctor will stop the transfusion to do further tests before deciding whether to continue. A febrile reaction can also occur shortly after the transfusion. Fever may be accompanied by chills and shaking.

Acute immune hemolytic reaction

This is a very rare but serious transfusion reaction in which your body attacks the transfused red blood cells because the donor blood type is not a good match. In response, your immune system attacks the transfused red blood cells, which are viewed as foreign. These destroyed cells release a substance into your blood that harms your kidneys. This usually occurs during or right after a transfusion. Signs and symptoms include fever, nausea, chills, lower back or chest pain, and dark urine.

Lung injury

Transfusion-related acute lung injury (TRALI) is thought to occur due to antibodies or other biologic substances in the blood components. With TRALI, the lungs become damaged, making it difficult to breathe. Usually, TRALI occurs within one to six hours of the transfusion. People usually recover, especially when treated quickly. Most people who die after TRALI were very sick before the transfusion.

Bloodborne infections

Blood banks screen donors for risk factors and test donated blood to reduce the risk of transfusion-related infections. Infections related to blood transfusion still rarely may occur. It can take weeks or months after a blood transfusion to determine that you've been infected with a virus, bacterium or parasite.

The National Institutes of Health offers the following estimates for the risk of a blood donation carrying an infectious disease:

  • HIV — 1 in 2 million donations, which is lower than the risk of being killed by lightning
  • Hepatitis B — 1 in 205,000 donations
  • Hepatitis C — 1 in 2 million donations

Delayed hemolytic reaction

This type of reaction is similar to an acute immune hemolytic reaction, but it occurs much more slowly. Your body gradually attacks the donor red blood cells. It could take one to four weeks to notice a decrease in red blood cell levels.

Iron overload

If you receive multiple blood transfusions, you may end up with too much iron in your blood. Iron overload (hemochromatosis) can damage parts of your body, including the liver and the heart. You may receive iron chelation therapy, which uses medication to remove excess iron.

Graft-versus-host disease

Transfusion-associated graft-versus-host disease is a very rare condition in which transfused white blood cells attack the recipient’s bone marrow. This disease is usually fatal. It is more likely to affect people with severely weakened immune systems, such as those being treated for leukemia or lymphoma. Signs and symptoms include fever, rash, diarrhea and abnormal liver function test results. Irradiating the blood before transfusing it reduces the risk.

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.

You don't need to change your activity levels or diet before a transfusion.

If you've had a reaction to prior blood transfusions, be sure to tell your doctor.

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

During the procedure

Before the transfusion begins, an identification check will be done to ensure you're being given the correct blood. Then an IV line with a needle is inserted into one of your blood vessels. The donated blood that's been stored in a plastic bag enters your bloodstream through the IV. A nurse will monitor you throughout the procedure.

Tell your nurse immediately if you develop:

  • Fever
  • Shortness of breath
  • Pain at the site of transfusion
  • Chills
  • Unusual itching
  • A sense of uneasiness

After the procedure

The needle and IV line will be removed. You may develop a small bruise around the IV site, but this should go away with time.

You may need further blood testing to see how your body is responding to the donor blood and to check if your blood counts have reached an appropriate level.

For example, if before the transfusion you were anemic, meaning you had low levels of red blood cells, your doctor will check to see how much the transfusion raised your red blood cell count.

Or, if you've had low platelets because of chemotherapy drugs, your doctor may test your blood to see whether the transfusion sufficiently boosted your platelet count. Some conditions require repeated blood transfusions.

April 01, 2015