What’s the difference between blood and plasma donation?

In the United States, blood donation is so standard that some high schools have student blood drives, yet only in the last couple of years has plasma donation surfaced in the news. Many people believe that donating blood and plasma are one and the same, and while both have you sitting in a chair hooked up to a machine, they are different processes with different purposes.

When people think of blood donation, they are typically thinking of whole blood donation. Whole blood donations include all four blood components–red blood cells, white blood cells, platelets, and plasma–and are used to treat blood loss, typically due to injury or surgery. 

In contrast, plasma donation involves collecting just one component of whole blood and returning the other three to the donor. Plasma is used to create different therapies to help replace missing, deficient, or malfunctioning proteins in individuals with serious, often life-threatening diseases, such as hemophilia and primary immunodeficiency. 

Right now, there is a global need for more plasma donations as the usage of plasma-based therapies is becoming more widely accepted for a larger number of disorders. 

Who is eligible to donate?

Both blood and plasma donations have similar eligibility guidelines. Donors must be over the age of 18 (with some centers capping the age of donation at 65), need to weigh at least 110 lbs., and be in good health. For blood donations, minors can donate blood with parental consent. 

There are other reasons a person may be ineligible to donate blood or plasma, including chronic illness, a new tattoo, IV drug users, and recent non-monogamous sex for men who have sex with men. Being disqualified for a chronic illness like primary immunodeficiency or hemophilia because it isn't safe for those individuals to donate plasma. 

One big difference between whole blood donation and plasma donation is how frequently you can donate. Plasma comprises about 90% water, so your body quickly replenishes its plasma supply within 48 hours. Plasma donors are eligible to donate plasma twice within a 7-day period and need only one full day between donations. In contrast, whole blood donors are required to wait 56 days between appointments because the other blood components–red blood cells, especially–take longer to replenish. Individuals with a new tattoo, IV drug users, and men who have non-monogamous sex with other men are at increased risk of carrying bloodborne viruses that can be transmitted by blood/plasma.

Recently, there have been a few eligibility requirements that have been relaxed. For example, in Australia, you can donate plasma right away after receiving a tattoo, as long as it was done in a licensed tattoo parlor in Australia. Another example is how all men who have sex with men were ineligible until recently, but that rule has been updated to be less discriminatory.

What’s the donation process like? 

The whole blood donation process is relatively simple, whereas plasma donation is more complex. Donating either blood or plasma begins with check-in for a valid ID and a health screening that includes a questionnaire about medical history and a vitals check from a medical professional. The vitals check includes temperature, blood pressure, pulse, weight, and a quick blood test to measure red blood cell and protein levels to ensure you’re healthy enough to donate that day. 

After check-in, the whole blood donation takes about ten minutes. During this time, a pint of blood is collected through an IV that is placed into a healthy vein in your arm and deposited in a medically safe blood bag. Donation center workers may also collect a small amount of blood in a vial for testing at this time. From there, donor center staff will bandage the arm, and you’re done. 

For first-time plasma donation, you must also pass a full physical and a medical history screening. Some plasma donation centers will do regular monthly screenings for their donors, while other centers do a wellness check at each visit. First-time visits for plasma donation can take much longer than return visits or any blood donation visit. This is because first-time plasma donors must complete a physical with donor center staff. 

After being approved through the health screening, you are hooked up to a plasmapheresis machine. While it may feel similar to blood donation to the donor, the process is quite different. First, it takes close to 60 minutes. Second, whole blood is taken through the plasmapheresis machine, where plasma is carefully separated from other blood components. The remaining blood components (red blood cells, white blood cells, and platelets) are returned to the body in a saline solution to help with hydration. Additionally, plasma donation involves two IVs. One is to take the blood into the plasmapheresis machine, and one is to return the remaining blood components in saline.

In the United States, plasma donors receive financial compensation for the time they spend in the donation center, whereas blood donors do not. A blood donor can complete the entire donation process in 30 minutes, whereas plasma donation requires a much more significant time commitment. This is why plasma donors are compensated while blood donors are not.

How are the donations processed?

Blood donations save millions of lives. In fact, according to the American Red Cross, approximately 29,000 units of red blood cells are needed every day in the United States. Once donated blood is at a processing center, the blood is spun in centrifuges to separate it into transfusable components–like red cells, platelets, and plasma–and white blood cells are removed to reduce the possibility of the recipient having an adverse reaction to the transfused blood. From there, your blood sample from the vial undergoes tests to establish blood type, any infectious diseases, and more. All blood is tested for Hepatitis B, Hepatitis C, HIV Types I and II, Human T-Lymphotropic Virus Types I and II, syphilis, West Nile virus, Chagas disease, Cytomegalovirus, Babesia, and bacterial contamination. If the results are positive for any diseases, the donation is discarded, and you–the donor–are notified. If the results from the tests come back normal, the blood is labeled and stored, and then distributed to hospitals for use. Blood donation is used for blood transfusions for injury, surgery, or illnesses like sickle cell disease. 

After plasma donation, the plasma is frozen at the donation center to await confirmation of tests ensuring the donor's safety and the health of the plasma; this includes similar screenings as blood undergoes for diseases, as well as testing for antibodies that the body produces in response to a virus. From there, it goes to a facility for production. In manufacturing, the plasma undergoes fractionation, which is a separation process in which the plasma is divided into smaller fractions with specific properties that are then purified for a specific protein–for example, one fraction is used for immunoglobulin, one is for albumin, one is for factor VIII, etc. The plasma is then used to create specific treatments, like immunoglobulin (Ig) replacement therapy or clotting factors. It can take approximately 12 months from donation until the product is available for patients.

Ready to save lives?

Whether you donate blood or plasma, you’re helping to save lives. If you’re interested in becoming a plasma donor, find a donation center near you!