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Blood Component Transfusions

What Are Blood Component Transfusions?

Blood component transfusions, also called blood transfusions, can improve a patient's condition. They can even save a patient’s life. Blood transfusions also come with some risks, just like many other medications. The number of patients who become very ill or die from a blood transfusion is very small when compared to the benefits that blood components can provide.

You should discuss with your doctor the specific need or reason for the blood component you or your child is about to receive.

Blood components are often used to replace elements of the blood that are missing or at low levels due to an injury or illness. These include red blood cells, platelets, plasma, cryoprecipitate and granulocytes.

Where Do Blood Components Come From?

Blood components are obtained from volunteer blood donors. Their blood is collected in a regulated manner and then separated into components. Blood donation centers typically allow blood to be donated by:

  • Anonymous donors
  • Family members or friends for a specific patient (directed donation)
  • A patient for themselves (autologous)
  • The vast majority of transfused blood is donated by anonymous people in the community. Rarely, blood can be donated by a patient and then transfused back to themselves when needed. Other times, a patient may ask others to donate blood specifically for them. Both of these have different risks from using anonymous donor blood, and these risks should be discussed with your doctor and the blood center collecting the blood.

Blood May be Processed into These Blood Components:

Packed Red Blood Cells (PRBCs)

Packed red blood cells have had most of the plasma removed from the whole blood. Packed cells are most often given into a vein over two to four hours. This is given to replace the red cells lost through bleeding, hemolysis (destruction of the red blood cells), or when the bone marrow produces fewer red cells. The decreased production of cells may be due to: bone marrow failure, cancer involving the marrow, the effect of chemotherapy drugs used to treat a cancer, or anemia due to prematurity. Red blood cells are necessary because they carry oxygen to the rest of the body.


Platelets are the cell fragments that help prevent or stop bleeding or bruising by plugging the hole in the blood vessel along with other clotting proteins. Platelets are most often given into a vein over one to two hours. They are rarely given continuously. Platelets may be given when a patient's platelets are not working the right way due to medicines, illness, mechanical damage (such as from an artificial heart valve), or if their bone marrow is not working due to disease or chemotherapy. Platelets are necessary in the body because they are an important part of forming a clot to stop bleeding.

Fresh Frozen Plasma (FFP)

Fresh frozen plasma is plasma that was frozen and stored shortly after it was obtained from the blood donor. It is thawed before infusion. It is most often given into a vein over one to two hours. Fresh frozen plasma is used when a patient is bleeding or is missing some of the clotting proteins. Fresh frozen plasma is important because it contains many clotting factors necessary to stop bleeding.

Cryoprecipitate (Cryo)

Cryoprecipitate is the part of the blood that contains only certain clotting factors: factor VIII, factor XIII, von Willebrand factor, and fibrinogen. It is stored frozen and thawed before infusion. It is usually given over one to two hours. Cryoprecipitate is used when a patient is missing one of the above components in their blood due to a genetic disorder or severe disease such as disseminated intravascular coagulation (DIC). Cryoprecipitate contains some important factors to make a clot in a concentrated product.

Reconstituted whole blood

Reconstituted whole blood is a product made from combining red blood cells and plasma to mimic the composition of human blood. This product is usually used for exchange transfusions for newborns who have high bilirubin levels or hemolysis/breaking down of red blood cells for various reasons. It can also be used to transfuse a fetus in severe cases of hemolysis.


A granulocyte product is made of neutrophils, the white blood cells that help fight infection. Granulocytes are occasionally given to help fight off severe infections in patients who have no neutrophils in their blood and have not responded to other medicines. Granulocytes are collected from anonymous donors after the donor takes a steroid medicine to help get the neutrophils to move into the blood for collection. Blood is collected using a cell separation machine (apheresis) that takes mostly white blood cells and returns the rest of the blood to the donor over several hours. Granulocytes are most often infused into a vein over one to two hours.

What Are Possible Risks of Use of a Blood Component?

Sometimes there are adverse reactions that occur with the use of a blood component. Most of these reactions are not common and get better by stopping the transfusion and sometimes giving additional medicines such as a fever reducer or antihistamine. If the reaction is severe, other treatments may be necessary including special processing of blood components before transfusion or giving medicines before a transfusion.

If a reaction occurs, the clinical team will stop the transfusion and send some of the patient’s blood to the blood bank for additional testing. A medical director will review the test results and discuss with the team the next steps needed for safe future transfusions. This process usually takes one to two hours but may take up to several hours or longer depending on what is discovered. Adverse reactions can be from an immune-mediated reason, non-immune-mediated reason, infection transmitted from the blood, or symptoms may be determined to not be related to the transfusion. These are explained below.

  • Immune-mediated adverse reactions can occur if a patient's immune system reacts to the blood component. It can also happen if the immune cells in the blood component react to the patient's cells or fluids. They may include:
    • Fever with no other symptoms (febrile non-hemolytic transfusion reaction)
    • Allergic reactions
    • Anaphylactic reaction
    • Development of red blood cell or platelet antibodies that can attack future transfused red blood cells or platelets
    • Damage to the lung tissues from antibodies in the transfused component (TRALI)
    • Hemolysis caused by antibodies in the patient, occurring days to weeks after the transfusion (delayed hemolytic transfusion reaction)
    • Graft versus host disease (TA-GVHD)
    • Purpura (bruising) from antibodies destroying platelets
  • Non-immune-mediated adverse reactions include:
    • Fluid overload (TACO)
    • Drop in blood pressure (hypotension)
    • Excess potassium being transfused, requiring treatment
    • Tingling of the hands and lips caused by lowered blood calcium level
    • An overload of iron in the body tissues, which is a concern for patients receiving many red blood cell transfusions over their lifetime
  • Infection
    • An infection could occur from the use of a blood component that contains bacteria, a virus (like Hepatitis B and C, HIV, or CMV) or a parasite
    • Transfusion of a granulocyte component is slightly riskier than other blood components. Since the white blood cells do not live long after collection, this component must be transfused soon after collection (as soon as possible within 24 hours). Because of this, these units are transfused before the infectious disease test results are available. Granulocyte donors have stricter requirements to donate compared to other blood component donors, and so are generally considered safe. The results of the testing will be communicated to your doctor as soon as they are available, usually the next day.

Some of these adverse reactions are prevented by modifying the component before transfusion, such as with irradiation (prevents TA-GVHD). Others are avoided by interviewing and testing blood donors (for infections). There is always a risk to receiving a blood transfusion. These risks usually do not outweigh the benefits of receiving blood.

Learn more about these risks by speaking with your healthcare team, by reading details of these adverse reactions and by visiting recommended websites.

Symptoms of a Possible Problem

Symptoms to watch for include:

  • Fever over 100.6°F (38°C) taken by mouth
  • Blood pressure changes
  • Chills, headache, belly aches, throwing up, loose stools or back pain
  • Dark-colored urine, yellowing of skin or eyes, sudden fatigue
  • Hives, itching, wheezing, shortness of breath, problems breathing
  • Swelling of feet or ankles, or a cough that was not there before the transfusion
  • Delayed reactions: In rare cases, a delayed reaction can happen days to weeks after a transfusion of red blood cells. Call your child's doctor if your child gets a fever, develops a new pain such as back pain, or becomes pale or jaundiced (yellow color in skin and whites of eyes) after a recent blood transfusion.

If your child has symptoms after receiving a blood product, call your nurse or doctor right away.


Sometimes there are other choices. Your health care team can talk to you about which ones may be used, based on your child's condition. Options include using medicines to avoid any blood products or using blood from people other than anonymous blood donors. These can include:

  • Drugs that can stimulate the bone marrow to make more red blood cells, white blood cells, or platelets.
  • Drugs that are specific concentrates of a clotting factor such as Factor VIII or IX concentrates, or by giving medicines that stop the breakdown of clots (tranexamic acid, aminocaproic acid) or increase the level of certain clotting factors (DDAVP). Medicines that specifically reverse certain anticoagulants (blood thinners).
  • For patients having some surgeries, their blood lost during the surgery due to bleeding may be collected during surgery and transfused back to the patient (intraoperative salvage procedure).

Directed Donation:

Having family and friends donate units to a specific patient is an option. But this is not the ideal way to provide blood to a patient for many reasons. Selected donors may have incompatible blood or may have blood that doesn’t pass testing, the unit of blood may accidentally break or go out of temperature during storage or transport, and the patient may still have a reaction from those units. If desired, patients can talk to their doctors for more information.

Generally, these requests must be done several weeks to months in advance and are completed by the local blood center for a fee. The patient also needs to decide if they will accept anonymous donor blood if not enough blood is collected or if their bleeding is severe and more units are needed. Also, some components such as FFP or cryoprecipitate cannot be collected for a direct donation. Please contact Hoxworth Blood Center for more information.

Autologous Donation:

Donating blood that will be transfused back to yourself is an option. This is not an ideal option for most people, though, especially for pediatric patients. Autologous units may have issues during processing that result in the unit becoming unusable, such as the bag breaking or becoming out of temperature. The patient must schedule the donation weeks to months in advance, which is collected at the blood center for a fee. The patient may also end up needing additional transfusions due to bleeding or other complications. The patient should decide ahead of time what to do if they require transfusion of anonymous donor blood. 

What Are Additional Resources to Learn More about Blood Components?

For more information about blood components, speak with your child's doctor. You can also find information on these websites:

Why Donate Blood Platelets

Last Updated 03/2024

Reviewed By Kristina Prus, MD