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Alberta Blood Transfusion Information

Blood transfusions: Frequently asked questions

​​​​​​​​​​​​​​​​​​​​​​​What is a blood transfusion?

  • A blood transfusion is when you’re given a blood product. A blood product can be red blood cells, plasma, or platelets. It can also be a product that is made from plasma.
  • A blood product is usually given through an intravenous (IV). An IV is a small tube or needle that’s put into a vein.
  • A blood transfusion is usually given slowly and can take up to 4 hours.

Why do I need a blood transfusion?

Your doctor will talk with you about why you or your child need a blood transfusion. Common reasons you may need a blood transfusion are if you:

  • lose blood in an accident or during an operation
  • don’t make enough blood
  • ​have parts of the blood that aren’t working the way they should
  • have certain medical conditions
  • ​get certain treatments, such as chemotherapy

What blood products can be transfused?

You or your child will only get the part of the blood that you need. The different parts of blood that can be transfused are:

Red Blood Cells

  • Red blood cells carry oxygen from your lungs to all parts of your body. Your heart, brain, kidneys, and all of the organs in your body need oxygen to work properly.


  • Platelets are small, sticky cells that make plugs on walls of your blood vessels (veins and arteries). This helps to prevent or stop bleeding.


  • Plasma is the clear, liquid part of blood that has proteins in it. These proteins help your blood to clot. Plasma can be given with platelets to prevent or stop bleeding.

Blood products made from plasma

Plasma can be used to make other blood products. These are used for special reasons to treat certain illnesses (such as factors for hemophilia) or help fight infections (such as immunoglobulins).

Where do blood products come from?

  • In Alberta, Canadian Blood Services (CBS) collects blood from healthy, volunteer donors. All donors are asked questions about their health, travel, and social history before blood is collected. This helps make sure that the blood is as safe as possible.
  • The blood that is donated is tested for different diseases. If there’s a problem, the donor is not allowed to give blood again. Blood that doesn’t pass testing is thrown away.
  • After the blood is tested, it’s separated into all of the different parts – red blood cells and platelets.
  • When you need a blood transfusion, a sample of your blood is taken. Tests are done on this blood sample to make sure the donated blood will match with your blood.

Are there risks when getting a blood transfusion?

Getting blood always has some risk. Your healthcare provider will explain the risks of transfusion specific to you or your child.

The blood supply in Canada is one of the safest in the world. The risk of getting diseases for each unit of blood is very low.

  • Human immunodeficiency virus (HIV) - 1 in 21 million
  • Hepatitis C - 1 in 13 million
  • Hepatitis B - 1 in 7.5 million

Can I have a reaction to a blood transfusion?

Sometimes you can react to a blood product transfusion. This is called a transfusion reaction.

To watch for this, your vitals (blood pressure, heart rate, breathing) will be checked often during the transfusion. If you or your child has ever had a reaction with a transfusion before, tell your healthcare team.

Some types of reactions are:

Allergic Reaction

  • This reaction is common. It’s usually mild, and usually causes itching or a rash. Very bad allergic reactions, such as breathing problems, are rare.

Fever Reaction

  • This reaction is not common. It usually happens during or shortly after a transfusion. This kind of reaction can cause fever, chills or warm, red skin (flushing).

Hemolytic Reaction

  • This reaction is rare. It can be dangerous. It happens when your blood attacks the transfused blood. The blood tests done before the transfusion help to lower the risk of this kind of reaction.​

Are there other options to having a blood transfusion?

Your healthcare provider will explain what other options may be appropriate for you or your child.

Blood Substitutes

  • There are some artificial clotting factors that can be used in certain bleeding conditions, such as hemophilia. These may be used instead of plasma or blood products.
  • There are no artificial blood substitutes for red blood cells or platelets.

Other Alternatives

  • Medicines like erythropoietin (EPO, Eprex) and iron can help your body make more red blood cells.
  • Medicines that help stop blood clots from breaking down can help slow down or stop bleeding.
  • IV fluids can increase the amount of fluid in your arteries and veins.
  • Special procedures can lower how much blood that you or your child lose during or after surgery.

If you have any questions or concerns, talk to your healthcare provider​.​​​​


Current as of: April 7, 2021

Author: Transfusion Medicine Safety Program, Alberta Health Services