Blood transfusions

Anaemia

Anaemia is a reduction in the number of red blood cells in the blood. Many people with cancer will develop it at some time during their illness. This can be due to the cancer or its treatment, including chemotherapy and radiotherapy. If the level of red blood cells (haemoglobin) in your blood is low, you may become very tired (lethargic) and feel that you have no energy. This is because the amount of oxygen being carried around your body has decreased. You may also become breathless.

You will have a blood test to check your haemoglobin level if you have symptoms of anaemia, or are having treatment for cancer. This is known as a full blood count (FBC). Your doctors may recommend that you have a blood transfusion if your haemoglobin level is low. A blood transfusion means that blood is given by a drip (infusion) into one of your veins. The blood contains extra red cells, which will pick up the oxygen from your lungs and take it around the body to other tissues and organs. You will then have more energy and the breathlessness will be eased.

Blood transfusions

There are different treatments for anaemia depending on what is causing it. Blood transfusions are a simple way of correcting anaemia. The symptoms of anaemia are often relieved quickly and you should notice a benefit 24 hours after having the transfusion. Transfusions may be used alone or together with other forms of treatment for anaemia. The beneficial effects of a blood transfusion can be temporary and some people may need further transfusions.

Having a blood transfusion

Before a blood transfusion is given, the blood must be cross-matched to ensure that it is compatible with your own blood. This involves taking a sample of your blood to identify your blood group, and matching it with suitable donor blood. This procedure ensures that the blood you are given will not make you unwell.

The transfusion itself involves a small tube, known as a cannula, being placed into a vein in your hand or arm. This is then connected to a drip. The blood is then run through the drip. Some people have a transfusion given through a larger tube put into a vein in the chest (a central line), or the crook of their arm (a PICC line).

Blood for transfusion is stored in small plastic bags. Each bag is called a unit of blood and is about a pint (half a litre). Transfusions usually involve giving 2–4 units depending on how anaemic you are. Each unit is given over a period of 1–2 hours. When the transfusion is finished the drip is taken down and the cannula can be removed.

If you need several units of blood you may need to stay in hospital overnight. However, a transfusion of only 1–2 units of blood can usually be given to you as a daypatient or outpatient.

Possible side effects

During the transfusion, you will have your temperature, pulse and blood pressure checked regularly by the nurses to detect any reaction to the blood. Common side effects that can occur are headaches, a slight rise in temperature, or a skin rash. These effects can be relieved by drugs such as paracetamol. Severe side effects from blood transfusions are rare because of cross-matching.

Many people worry that they may get an infection from a blood transfusion. All blood is carefully screened before use and infections are extremely rare.

Having more than one transfusion

Many people will need only one or two transfusions during their illness, although it is possible to have repeated transfusions if necessary. If you need to have lots of blood transfusions over many months, there is a very small risk of iron overload. This is because the red blood cells in each unit of blood contain a small amount of iron.

Iron overload is a potentially harmful situation and treatment may be needed to help stop this from occurring. Your doctor or nurse will explain more about this treatment if it is necessary.

Are blood transfusions safe?

Some people worry that the blood they are given may be infected by disease. People who donate blood and platelets are carefully screened to assess their risk of having an infection or virus, such as HIV, hepatitis or malaria. This means that the risk of being given infected blood is extremely small.

There have been no reports of CJD (Creutzfeldt-Jakob disease) infection due to blood or platelet transfusion. Precautions are taken to minimise the risk of infection. All donated blood is tested in the laboratory for infection. Blood is not given to a patient until all tests are found to be negative.

Platelet transfusions

Most transfusions are given to correct anaemia, but occasionally transfusions of platelets may be given to help the blood to clot and prevent bleeding. If the number of platelets in your blood is low you may bruise easily and bleed heavily even from minor cuts or bruises.

People with leukaemia, people who have had high doses of chemotherapy and those who have had a bone marrow transplant commonly have low platelet counts and may need to have platelet transfusions. Normally 1–3 units of platelets are given at a time. Platelets can be infused over a shorter time than blood and each unit usually takes approximately 15–30 minutes.

References

This section has been compiled using information from a number of reliable sources including:

• Oxford Textbook of Oncology (2nd edition). Souhami et al. Oxford University Press, 2002.
• Oxford Textbook of Palliative Medicine (3rd edition). Doyle et al. Oxford University Press, 2004.

For further references, please see the general bibliography.

Via: http://www.cancerbackup.org.uk