Blood Transfusions
Blood transfusions (or blood product transfusions) temporarily replace parts of your blood when your body can't make them on its own or loses them from bleeding. Learn more about blood products, how they are donated and transfused, and their role in cancer care.
What is a blood transfusion?
A blood transfusion is a procedure that puts blood or parts of blood from a donor into your blood. It is given as a transfusion through an intravenous (IV) line placed into a vein.
You might also hear this called a blood product transfusion. Or your care team might refer to the type of blood product by name. See Types of Blood Products below.
Why do people with cancer need blood transfusions?
People with cancer may need blood transfusions because:
- Some cancers cause bleeding inside the body (internal bleeding).
- Blood cancers (like leukemia) can crowd out healthy blood cells in the bone marrow.
- People who’ve had cancer for a while may develop anemia of chronic disease.
- Certain cancers can affect organs like the liver and spleen.
Some people may need blood transfusions because of side effects from cancer treatment, such as:
- Low blood counts from chemotherapy (chemo) and radiation
- Bleeding after surgery
Types of blood products
Blood donors usually give whole blood, which can then be separated into parts called blood products. Each part does a separate job.
Whole-blood transfusions are usually saved for emergencies like trauma or surgery, where there is severe blood loss that needs to be replaced quickly. When possible, a single unit of whole blood is used to help more than 1 person. Each person only gets the part of blood that they need.
The types of blood products (parts) are:
- Packed red blood cells (PRBCs)
- Platelets
- Fresh frozen plasma (FFP) or plasma
- Cryoprecipitate (cryo)
Red blood cells (RBCs) are cells in the blood that carry oxygen and deliver it throughout your body. Packed red blood cells (PRBCs) are prepared by separating RBCs from the blood and removing most of the plasma (the liquid part of blood).
Sometimes, white blood cells are also removed. What is left is called leukocyte-reduced red blood cells. Leukocyte-reduced RBCs may be used for people with a higher risk of reacting to a transfusion.
When are packed red blood cell transfusions used in cancer care?
Surgery: You might get a transfusion before, during, or after surgery if you have low blood counts or to make up for blood loss.
Anemia: Low numbers of RBCs cause anemia. People with anemia may need RBC transfusions because they don’t have enough hemoglobin (the protein on red blood cells that carries oxygen throughout your body).
Common causes of anemia in people with cancer include:
- Cancer treatments like chemo or radiation that kill RBCs
- Blood cancers like leukemia where cancer cells crowd out RBCs
- Some tumors that make it hard for the body to make RBCs
- Low iron or vitamin B12 levels
A normal hemoglobin (Hgb) level is about 12 to 18 g/dL.
You may get an RBC transfusion if your hemoglobin is less than 8 g/dL. It will also depend on your symptoms and how long it takes for the anemia to develop.
Anemia from a sudden loss of blood usually needs to be addressed right away. Anemia that develops slowly is less likely to cause problems, because your body has time to adjust. If your hemoglobin level is lower than normal but you aren’t dizzy, pale, or short of breath, you may not need a transfusion.
Platelets are pieces of cells in your blood that help make clots and stop bleeding.
A unit of whole blood has only a small number of platelets. So, it takes platelets from several units of whole blood to help keep a person from bleeding.
Platelets don’t have a blood type like red blood cells do, so you can usually get platelets from any donor. The donor doesn’t always need to match your blood type.
Pooled platelets: For this platelet transfusion, 6 to 10 units from different donors (called random donor platelets) are combined and given to an adult patient at one time. When they are combined like this, they are called pooled platelets.
Single donor platelets: Platelets can also be collected by apheresis (or plateletpheresis). A donor is hooked up to a machine that removes their blood and keeps only the platelets. The rest of the blood cells and plasma are returned to the donor. This method can collect enough platelets from a single donor, so they don’t have to be combined with platelets from multiple donors.
When are platelet transfusions used in cancer care?
You may need platelet transfusions if your bone marrow doesn’t make enough platelets.
In people with cancer, this can happen:
- When chemo or other cancer treatments damage the bone marrow (where blood cells are made)
- In certain blood cancers (like leukemias) when cancer cells in the bone marrow crowd out normal blood cells
A normal platelet count is about 150,000 to 400,000 platelets per microliter (mcL) of blood.
When platelet counts are below a certain level (often 20,000/mcL), you are at risk for serious bleeding. You might get a platelet transfusion when your platelet count is below this level or even at higher levels if you are bleeding or need surgery.
If there are no signs of bleeding, you might not need a platelet transfusion even if your platelet count is low.
Plasma is the liquid part of blood. It has proteins called clotting factors that help blood clot. Clots help stop bleeding when we’re injured. Plasma has other proteins, like antibodies, that help fight infection.
After plasma is separated from the RBCs, it can be frozen and kept for up to a year. Once thawed, it’s called fresh frozen plasma (FFP).
When are plasma transfusions used in cancer care?
You may get an FFP transfusion if you:
- Are bleeding because your blood doesn't clot the way it should
- Have a condition called disseminated intravascular coagulation (DIC)
In DIC, all the clotting factors in the body are used up. Signs and symptoms (like severe bleeding and bruising) and blood tests help doctors diagnose DIC.
Cryoprecipitate (cryo) is the part of plasma that separates out (precipitates) when plasma is frozen and then thawed. It has some of the clotting factors found in plasma, but they are concentrated in a smaller amount of liquid. A unit of whole blood has only a small amount of cryo, so about 8 to 10 units are pooled together for one transfusion.
When are cryo transfusions used in cancer care?
You may get a cryo transfusion to replace missing blood clotting factors like:
- Factor VIII (missing in people with hemophilia A)
- Von Willebrand factor (needed to help platelets work)
- Fibrinogen (protein needed to form a clot)
Other treatments
You might get other treatments to help decrease the number of blood product transfusions you need. These treatments don’t replace blood transfusions.
When you lose a lot of fluid, your body can go into shock. It may be treated or prevented by giving fluids into a vein. This can help increase blood going to your internal organs, but these fluids don’t carry oxygen or raise the number of blood cells.
Iron helps your body make hemoglobin (Hgb). Some people with cancer and anemia have low iron levels. Iron supplements might help increase your hemoglobin and reduce the need for blood transfusions. This can be helpful if you have chronic anemia.
There are possible problems with taking iron, including a risk of iron overload (when iron levels in your blood get too high). This can damage some organs, so your health care team will monitor for this.
Your body naturally makes hormone-like substances called hematopoietic growth factors. These cause your bone marrow to make more blood cells. You might get a man-made version of growth factors to increase your red blood cell, white blood cell, or platelet counts.
Growth factors may be used instead of transfusions, but there are some limitations:
- Time: They often take days or weeks to increase blood counts, so they may not help if you need your blood cell levels raised quickly (for example, if you are bleeding).
- Effectiveness for some people: They might not work in people with severe bone marrow disease. Growth factors can’t work if there aren’t enough blood-producing cells in the bone marrow.
- Cancer growth: They might cause certain types of cancer cells to grow more quickly, including lymphocytic leukemia, multiple myeloma, head and neck cancers, breast cancer, cervical cancer, and some kinds of lung cancer cells.
- Cost: Growth factors usually cost a lot more than blood transfusions.
Because of these problems, some growth factors are not used in people whose treatment is expected to get rid of their cancer. When they are used, they are given for as short a time as possible.
So far, there is no real substitute for human blood. But researchers are working to develop a liquid that can carry oxygen and replace blood, at least for a short time.
Certain products being tested can do some of the work of red blood cells, like carrying oxygen to tissues, but can’t replace the many other functions of human blood.
Getting a blood transfusion
Most blood transfusions are given in a clinic or hospital. Depending on where you get the transfusion, the process may be a little different.
What to expect
Some of these (like informed consent) might not apply in a life-threatening emergency. But in general, this is what you can expect if you get a blood transfusion.
Before your transfusion:
- Your health care team will tell you why you need blood products. They will discuss the risks, benefits, and other options you might have.
- You will read and sign an informed consent (permission) form, saying you understand and agree to the transfusion.
- The lab will check your blood type. You might also get other blood tests, like testing for antibodies.
- The blood bank will find a donated blood product that matches your blood type.
When the blood product is ready, your health care team will:
- Check your blood pressure, heart rate, and temperature
- Place an intravenous line (IV) in your arm if you don’t already have an IV or central line
- Do safety checks to make sure the blood product is the right one for you
- Remind you about the signs of a transfusion reaction and what to watch for
During your transfusion:
- The nurse will start the transfusion in your vein slowly for the first 15 minutes or so. This is to make sure you don’t have a reaction.
- After about 15 minutes, they will increase the rate of the transfusion.
How long does a blood transfusion take?
How long the transfusion takes depends on what kind of blood product you get and how your body reacts to the transfusion.
- Whole blood and PRBCs take between 2 to 4 hours to complete.
- Platelets and plasma can be transfused quickly, usually in less than 30 minutes.
If you have certain conditions like heart failure, your health care team may run the transfusion more slowly so your body doesn’t get too much fluid at once.
Are transfusions ever given at home?
Rarely, transfusions can be given at home by a visiting nurse. There are certain rules on who can and can’t get a transfusion at home. Home transfusions follow the same safety standards as hospital transfusions. Not all home health agencies provide this service.
Can you donate your own blood for your transfusion?
Donating your own blood for later use is called autologous donation.
This is most often done in the weeks before a scheduled surgery that will likely require a blood transfusion. Your own blood can then be used during or after the surgery to replace any blood you lose.
This is thought to be the safest form of blood transfusion. Still, it’s not totally without risk. There’s always a very small chance of bacterial contamination or clerical errors. Your health care team also needs to plan so that your blood cell counts go back to normal before surgery.
Check with your insurance about costs. Not all insurance plans cover the fees for this type of blood donation.
Learn more
- Written by
- References
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing.
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