What Happens When I give Blood?

Donating blood is simple.

Welcome and Preparation
Health Screening
Your donation
After donation refreshment
At home

To see what happens view our blood donor experience video.

Welcome and Preparation

Before donating blood, please eat regular meals, drink plenty of fluid (non-alcoholic) and avoid vigorous exercise or exertion. When you attend your donation session please read our Welcome leaflet provided. This explains the importance of Blood Safety. It’s important to read this whenever you attend because advice does change. We must give you sufficient information so that you can make an informed choice, on the benefits and risks of donating blood and samples for testing. We will provide 500ml of fluid just before you donate. By drinking this over about five minutes, it will help with your wellbeing during and after donation.

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Health screening

You will be called for private health screening, where a donor carer will confirm your identity. It’s critical that we guarantee an accurate link between you, your Donor Health Check and your donation. We must ensure that it's safe for you to donate and your donation is safe for a patient to receive. We’ll ask some confidential questions based on your completed Donor Health Check. There is a period of time from contact with any infection to detecting markers in the laboratory. We trust your honesty when answering these personal questions. This will ensure your blood is safe to transfuse to patients.

You may be referred to a registered nurse for certain medical queries. Their uniforms have red piping on the collar and cuffs. An explanation will always be provided if you are not able to donate. You will be advised when you can donate, and we’ll encourage you to make an appointment before you leave. For your wellbeing, we must ensure you have enough haemoglobin (iron) in your blood before donating. A small blood sample will be taken from your finger to test your haemoglobin levels. If your test is borderline, we will offer you a confirmatory test. This requires a sample of blood from your arm, to be tested in a machine at the session. We will advise you of the result.

Following health screening, you will be asked to sit in a different waiting area. From here you’ll be called and escorted to a donation chair.

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Your donation

When you are comfortable on the chair, you will be asked your name, address and date of birth again. Blood bags and sample tubes are labelled with unique donor identification numbers. All collection equipment is single use and sterile; only one blood bag is filled with your donation.

A blood pressure cuff will be placed on your arm to maintain a small amount of pressure during your donation. The cuff is not used to measure blood pressure. Your arm will be thoroughly examined to find a suitable vein before being cleaned with an antiseptic sponge. This kills normal bacteria (germs) on the skin. You will see staff cleaning their hands frequently, using hand wipes or gels.

Donors are advised to do applied muscle tension exercises during donation. This is to maintain blood pressure and promote wellbeing during and after donation. Following needle insertion you should be comfortable during your donation. If you experience any discomfort or pain please alert a member of staff.

An agitator scale constantly weighs and measures your donation. It will stop automatically when your donation is complete. Donor carers will be available to you throughout your donation. You may hear bleeping noises from the agitator, these inform us of the progress of your donation. A full donation is 470ml and will usually take between 5 and 10 minutes. If you require assistance or have any concerns, please make us aware by raising your non-donation arm.

After donation, the needle will be removed and a sterile dressing applied to your arm. We advise that you leave the pressure roll on for 30 minutes and the plaster dressing on for six hours. Please avoid using this arm to push on or to carry anything heavy. We will give you a card at the end of your donation with important care advice.

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After donation refreshment

A selection of drinks and snacks are available at the refreshment table. We encourage donors to relax here for at least 15 minutes and to have at least two drinks following donation.

If you feel unwell, please remain seated and alert a member of staff immediately. Where possible, we encourage you to book an appointment for your next donation.

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At home

If you become unwell (other than a cold or cold-sore) within two weeks following your donation, or if you believe there is a reason your blood should not be transfused to a patient, please call our donor helpline on 0300 123 23 23.

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