The availability of blood for operations and transfusions is an essential part of our health care system. Doctors and surgeons rely on blood donations to carry out urgent treatment and to save lives. Components extracted from the blood, such as plasma, are also important in treating burns or preventing infection.
Only 5% of the population currently donate blood, but the need for blood transfusions is increasing with surgical advances. Nearly three million donations a year are needed in the United States of America alone to keep pace with the increasing number of operations that are carried out.
Hospitals throughout the country need supplies of all types of blood, not just the rare blood groups. The commoner the blood type, the greater the demand for it.
Blood groups O and A are by far the most common in the United States, with 88% of the population having one of these blood types. Group B is far less common, and only occurs in 9% of people. Blood group AB is even rarer. Only 3% of the population have this blood type.
When can you donate your blood?
You can donate blood every 16 weeks. Regular donors usually make donations two or three times a year. This allows your body time to build up its stores of iron before the next donation.
On the day that you donate blood, you should drink plenty of liquid (but not alcohol). It is also important to eat regular meals and let the nurse know if you have missed a meal or are on a diet.
How it is performed
Blood donor sessions take place all over the country throughout the year. Many donor units are mobile, and there are often several donor centers within large cities. Telephone the National Blood Service on 0345 711 711 to make an appointment at your local center, or visit their website for details.
Your session will last about an hour.
When you arrive, a detailed health interview will be conducted, which is completely confidential. If you choose to make subsequent donations, the interview will be much shorter and consist of a few routine health questions. The nurse will then take a drop of blood from your finger or ear lobe to check that you are not anemic.
If the level of iron in your blood is too low, it may not be safe for you to make a full donation on that day.
The donation itself lasts about ten minutes, in which time 450ml (around three quarters of a pint) of blood is taken. A sterile needle is inserted in a vein at the elbow and discarded after a single use – they cannot transmit infection. After a short rest, a drink, and a biscuit, you will be ready to leave.
With your agreement, the blood you donate will be tested to find out your blood group and screen for any infection. If the tests reveal a problem, you will be informed in confidence and advised of whom to consult.
It is also important to let the donor center know if you develop any illness during the fortnight following a donation.
Often, there is a need for certain components of the blood, such as platelets. Apheresis is a specialised service where donors are hooked up to automated cell separator machines. These machines separate the blood into all its various components. All this is done during the course of the donation procedure.
When whole blood is extracted from the donor’s arm, the required part- e.g. platelets- is immediately separated, and the remaining blood cells are returned to the other arm. Because the large majority of blood components are returned, the donor can safely give blood again sooner than the average 16 weeks. In some cases, this can be every two weeks.
What is donated blood used for
- Blood donations are used for a number of purposes:
- Whole blood is used in cases of acute blood loss, such as after accidents or during an operation.
- Red blood cells are transfused when an illness leads to anemia.
- Platelets are needed where bone marrow cannot work properly following anti-cancer treatment, or in patients who cannot produce normal platelets to clot the blood.
- White blood cells are important to help patients whose resistance to serious infection is low, such as during cancer treatment.
- Plasma is used for critically ill patients who have lost a large volume of blood and need a replacement of the full range of proteins contained in plasma.
Who can use donated blood?
Nearly everyone who is aged between 17 and 60, weighs over 50kg, and is in good general health, can give blood. A confidential health interview before your first session is necessary to check that you are fit to give blood and that your blood is safe for the patients who receive it.
The nurse will ask you a number of questions that are designed to prevent the transmission of infection. This includes diseases such as HIV (AIDS), malaria, and glandular fever. If you are unwell on the day, (eg with flu or a cold), you will not be able to give blood.
Tattooing, body piercing or acupuncture, if done within the previous 12 months, are further reasons why you might be declined for donation. You will usually have to wait one year for the slight risk of infection developing to pass, before you are able to give blood.
If you have recently been taking antibiotics, you will have to wait a week until you have finished them.
Pregnant women should not give blood until at least six weeks after the baby has been born. If you received a blood transfusion or other blood products you must wait 12 months. Breastfeeding mothers can give blood provided they are not anemic.
Changes to legislation in the UK mean that from 5th April 2004, people who have had a blood transfusion since 1980 will no longer be able to donate blood. The new rules have been enforced to further reduce the risk of vCJD (variant Creutzfeldt-Jakob disease) being transmitted in blood and blood products.
All blood donations are tested thoroughly for dangerous viruses, but it is not always possible to detect them at the earliest stage of the infection. Very occasionally, viruses such as HIV and hepatitis B and C can take up to a year after someone is infected to show up in tests. This means that blood that does not show any signs of infection could still pass on a disease.
You should never give blood if:
- you or your partner are HIV positive,
- you carry the hepatitis B or C virus,
- you have ever worked as a prostitute,
- you are a man who has had sex with another man, even using a condom, or
- you have ever injected yourself with drugs, even once.
You should not give blood if you think you need a test for HIV or hepatitis, or if you have had sex in the past year with someone you think may by HIV or hepatitis positive. If you are worried you may be at risk, you can talk to the nurse or doctor at the donor center in complete confidence.