A Step by Step Guide to Blood Donation

By Roxanne Batty

Ever wondered about donating blood, but unsure of the process? Or maybe you have donated blood, but you want to know where the blood goes or how it is used. Leaping into the unknown can be an unnerving process, so we at BloodLink felt it might be useful for you to get a simple breakdown of the steps involved.

Step 1: The test

The donor, lets call him Gaurav, goes into a room where he is asked to sit down in the donation area. He is asked some basic health questions, and a small sample of Gaurav’s blood is taken to assess whether he is healthy enough to give blood that day.

Luckily, Gaurav is healthy. He has not had alcohol for 24 hours, or taken any drugs, so he can donate blood.

Want to check if you can donate blood? Take our short quiz on blood donation!

Step 2: The Donation

Blood can be donated in a few different ways. “Whole blood donation” is the most common type. This means that your blood is not broken down into any of its parts whilst it is taken.

A phlebotomist (a person trained to take blood) sterilizes Gaurav’s arm before drawing around 500ml blood. This only takes around 10 minutes. All materials used during each donation are pre-packaged, sterile and safely disposed of after use. Gaurav is then given refreshments and sits for a short period of time before he goes on with his day.

Step 3: Storing the Blood


Blood has to be stored in a certain way to protect it from damage. Gaurav’s blood is collected in special blood bags, which are coated with anticoagulation factors to stop the blood from clotting. These bags are designed to make sure that the blood is stored safely and can be transported.

A small sample of his blood is also sent for testing. This is a very important step, as there are certain diseases such as HIV and hepatitis B & C that can be transmitted to a person receiving blood. It also means that donors like Gaurav can become aware of any illnesses they may have.

Step 4: Blood Fractionation


Gaurav’s blood is then fractionated, meaning it is separated into its smaller parts. These include: proteins, red blood cells and plasma. In order to access these parts, the blood is centrifuged (spun at a really high speed) until it seperates. There are around 15 proteins in blood that can be separated. Often these proteins save the lives of those affected by trauma, disease or genetic illnesses.

What’s in the plasma?

Plasma is the blood component left once all the blood cells are removed from whole blood. It is the pale yellow liquid part of blood. Plasma makes up 55% of the bloods volume,  and is mostly (92%) water. It is stored frozen and thawed when needed.

The plasma contains the most important proteins. These include:

  • Factor VIII (used for the treatment of Haemophilia A, a disease that causes excessive bleeding)
  • Immunoglobulins (some of which are used to treat Guillain-Barre syndrome, a type of muscle-weakness damaging the peripheral nervous system).

The plasma can also undergo a process called “cryoprecipitation”. This is where fresh plasma is frozen and then centrifuged. This allows two different portions to be separated: the cryoprecipitate and the cryo-poor plasma.

The Cryoprecipitate Plasma

The cryoprecipitate undergoes viral inactivation and several purification steps. This ensures that the blood is safe and that any viruses are no longer active. Cryoprecipitate contains important proteins needed for clotting.

Who needs cryoprecipitate?

You may need a cryoprecipitate transfusion if you have low levels of some clotting proteins, in particular one called fibrinogen. Clotting proteins work together to help control bleeding or reduce the risk of bleeding. The most common use of cryoprecipitate is for a patient needing a large number of blood components at one time – commonly called a massive transfusion.

The Cryo-Poor Plasma (AKA Cryodepleted Plasma)

Cryo-poor plasma is the plasma remaining after some blood clotting proteins (cryoprecipitate) have been removed from fresh frozen plasma. The cryo-poor plasma also undergoes several steps before it is ready for medical use, such as viral inactivation and nanofiltration. This again makes sure that the plasma is safe.

Who needs cryo-poor plasma? You may need a cryo-poor plasma transfusion if you have Thrombotic Thrombocytopenic Purpura (TTP). TTP is a blood disorder that causes blood clots to form in small blood vessels around your body. Therefore, unlike those who have a cryoprecipitate transfusion, blood clotting proteins are not needed. The usual treatment for TTP is plasma exchange where some of your plasma is removed and replaced with cryo-poor plasma.

Step 5: Storing and transportation.

Both cryoprecipitate and cryo-poor  plasma are frozen and thawed when needed. They can be kept for up to a year.

Other parts of the blood include platelets, that are kept at room temperature and last for 5 days. Whole blood is kept refrigerated and can last for 42 days.

Step 6: Saving lives!

All the different parts of Gaurav’s blood can be used for different people with different needs. Whole blood can be used for people with anemia, or people who have lost blood through surgery or childbirth. Platelets can save the lives of those who need an organ transplant or chemotherapy. Cryoprecipitate and plasma can help those with trauma injuries, or going through surgery. Through one simple act, donating blood, Gaurav has become a life saver!


2017-02-06T17:17:27+00:00 Blood Donation|