What’s my blood type? How can I donate? Everything you need to know about giving blood

Experts from NHS Blood and Transplant provide valuable insight around giving blood.

The NHS has issued an urgent plea for blood donors following last week’s cyber attack
A man giving blood The NHS has issued an urgent plea for blood donors following last week’s cyber attack (Alamy Stock Photo)

The NHS has issued an urgent plea for blood donors following a cyber attack which affected several major hospitals in London last week.

King’s College Hospital and Guy’s and St Thomas’ declared a “critical incident” after pathology firm Synnovis was attacked. This disruption led to serious IT issues which caused cancelled operations and tests.

Affected hospitals cannot currently match patients’ blood at the same frequency as usual, NHS Blood and Transplant (NHSBT) said, sparking a national appeal for O blood type donors.

Donating blood can seem like a daunting prospect for many people, so we have spoken to some experts to unravel some of the commonly asked questions around the topic…

What is the criteria for donating blood?

According to the NHS, most people between the age of 17 and 65 are eligible blood donors.

The main criterias are to be generally fit and well, to weigh between 7 stone 12 lbs (50kg) and 25 stone (158kg) and to have suitable veins. However, those who have or have had cancer, heart conditions, organ transplant are among those who are not eligible to donate.

In addition, those who have received blood, platelets, plasma or any other blood products after January 1, 1980, have tested positive for HIV, are a hepatitis B or C carrier or have injected non-prescribed drugs including body-building and injectable tanning agents are also not allowed to donate blood.

People who feel ill during their appointment, are pregnant or who have recently got a tattoo or piercing may also be turned away.

Ella Poppitt, chief nurse for blood donation at NHS Blood and Transplant (NHSBT), has advised those wanting to donate to keep an eye on latest rules online as they might change.

“We are urging people of all backgrounds to come along to one of our centres to donate blood, it is a really rewarding thing to do,” Poppitt said.

“It is not something to be scared of and it is a great way to give back to the NHS. Lots of people come out of their appointments and say it was a really positive experience for them.”

Woman looking at her phone while sitting on a medical chair near transfusion machine while donating blood
Woman looking at her phone while sitting on a medical chair near transfusion machine while donating blood (Alamy Stock Photo)

Why is the NHS looking for O blood type donors specifically?

An appeal has been launched for O blood type donors because it is known as the universal blood type.

“Hospitals need O negative blood because it is the most common blood type used in emergencies for transfusions when the blood type is unknown as it can be given to anyone,” said Suzi Browne, a spokeswoman from the NHSBT.

“O positive is the most common type of blood in the UK so there is a big demand for it as it is used in the bulk of blood transfusions.”

Some people can find out what their blood type is by looking at their medical history, otherwise all blood donors will be told what theirs is after their blood has been processed.

What is the process of donating blood like?

There are 25 permanent blood donation centres in major towns and cities across the UK which are often open at evenings and weekends. The NHS also holds mobile donation sessions at community venues such as church halls.

According to the NHS, the whole donation process including preparation and recovery time takes around an hour. Upon entering a donor centre, donors must complete a safety check form and read a consent booklet which explains the importance of blood safety.

Poppitt said this is the best time to flag up any concerns with staff on standby.

“Our staff are really good at taking care of people throughout the process,” she said. “If you are feeling anxious, let them know that when you arrive and they can talk you through the process to alleviate any anxiety.

“We always provide donors with 500ml of fluid and a snack if needed just before they give blood. The blood transfusion process removes fluid from the body so we want to make sure donors keep hydrated.”

Donors are then asked to confirm their name, address and date of birth before the nurse puts a cuff around one arm to maintain a small amount of pressure during donation.

They will then find a suitable vein and clean it with an antiseptic sponge. A needle is then inserted into the chosen arm which collects the blood into a blood bag with a unique donor number.

A scale weighs the blood and stops once it is at 470ml (or just under a pint) – this process usually takes between five to 10 minutes. After the needle is removed, a sterile dressing is put on, and you’ll be encouraged to rest for a short time afterwards, having at least two drinks and a snack.

All donors are encourage to stay hydrated throughout the process
All donors are encourage to stay hydrated throughout the process (Alamy Stock Photo)

“Most people feel fine after giving blood, but if you need to sit and recover for some time afterwards that is fine too,” Poppitt said.

“A lot of the panic comes from the fear of the unknown. Most people say that the process is painless and was not what like they expected. Many leave with a good feeling that they have helped others.

“All donors are sent a text which tells them which hospital their blood has gone to, which is a really rewarding part of the experience.”

How can I prepare myself to donate blood?

“We recommend that all donors should arrive hydrated and fed before their appointment to maximise the chances of donating successfully,” Browne advised.

“A lot of people arrive in a rush but we encourage people to slow down.”

Poppitt added that donors should also avoid doing rigorous exercise before their appointment and should not drink lots of alcohol the morning of or the night before. You might also want to take it easy immediately after the appointment too, to give your body time to recover.

For more information search GiveBlood online and on social media, or visit