Frequently asked questions about blood transfusions

This leaflet gives information about blood transfusions. We hope to answer your concerns by concentrating on the most commonly asked questions. If you have any more questions please ask your doctor or nurse.

1 Who might need a blood transfusion?

Blood transfusions are used to treat anaemia (lack of red blood cells). Anaemia is quite common in people with cancer and other serious illnesses. It can cause weakness, fatigue, dizziness and shortness of breath. A blood transfusion may help you with these symptoms.

2 Are transfusions safe?

Almost always, yes. The main risk from a transfusion is being given blood of the wrong blood group. A smaller risk is catching an infection. To ensure you receive the right blood, the clinical staff make careful identification checks before any transfusion. They will ask you to state your full name and date of birth. They will regularly monitor you during your transfusion and ask you how you feel.

In the United Kingdom the authorities take many precautions to ensure blood is as safe as possible:

  • all blood donors are unpaid volunteers whose health is carefully checked
  • all donors are asked a number of questions to help rule out anyone who may pass on an infection
  • every donor is tested for certain infections each time they give blood
  • any donated blood that fails these tests is discarded
  • the testing process is checked regularly to make sure that it meets very high standards.

3 What is the risk of infection?

The most important of possible infections are hepatitis C, hepatitis B and HIV (the virus that causes AIDS and serious infections).

The risk of catching hepatitis from a blood transfusion is very low – about one in 900,000 for hepatitis B and less than one in 30 million for hepatitis C.

The chance of HIV infection is less than one in several million. As yet, we don’t know the level of risk of variant Crentzfeldt-Jakob Disease (VCJD) being transmitted by blood. However, there are rigorous procedures in place for minimising any risk of infection.

Thanks to these key measures and others, blood is now safer than ever before. Donated blood will be specially selected to match your own blood group. Fortunately, severe reactions to blood transfusions are extremely rare but, when they do occur, staff are trained to recognise them and will give you the treatment you need.

If you carry a card showing that you have had a previous reaction to a blood transfusion, please show it to your St Christopher’s nurse.

4 How is blood given?

It is dripped into a vein, usually in your arm or hand, using a needle and tubing. One bag of blood (a unit) takes about three hours to give (but can be given more quickly or more slowly if needed).

5 How will I feel during my blood transfusion?

Most people feel no different at all during their transfusion. However, some people develop a slight fever, chills or a rash. These are usually due to a mild immune reaction or allergy and are easily treated with paracetamol (Panadol) or by giving the blood more slowly. Most people find that it takes a few days before they feel the full benefit of the transfusion. The nurses or doctors from St Christopher’s will check with you whether the transfusion has helped or not. They will then be able to advise you regarding future transfusions.

6 How long will I need to stay?

Most people who have to have a transfusion will need two to three units of blood. This usually means staying at St Christopher’s overnight.

7 Can I choose whether to have a blood transfusion at St Christopher’s or elsewhere?

Yes. You may want to have your transfusion at the hospital that has been treating you. Your GP or district nurse can arrange this, as can the nurse from St Christopher’s.

8 What if I have other worries about transfusion?

You may be afraid of needles, worried about being squeamish at the sight of blood or have had a bad experience related to a blood transfusion. Please tell your doctor or nurse about any concerns you may have, no matter how small. Our doctors and nurses will answer your questions and talk through any worries with you or your family or friends. The St Christopher’s phone number is 020 8768 4500.

It is really important for your care that the information you give us is as full and accurate as possible.

The National Blood Service (NBS)

The NBS is part of the National Health Service (NHS) and provides the blood that patients receive. In order to plan for future blood demands, information about which patients receive blood needs to be gathered. The NBS may ask an NHS Trust or GP to provide limited medical information on a sample of patients who have received blood transfusions. Any information that is passed to the NBS is held securely, with the rights of these individuals protected under the Data Protection Act.

If you are interested in finding out more about blood transfusions and have internet access, you might find their website useful – visit*. If you do not have internet access, you can find out more about the NBS by phoning 0845 7 711 711.