Table of ContentsView AllTable of ContentsRole and CompositionBlood Plasma UsesBlood vs. Plasma DonationHow Machines Separate PlasmaPlasma Regeneration
Table of ContentsView All
View All
Table of Contents
Role and Composition
Blood Plasma Uses
Blood vs. Plasma Donation
How Machines Separate Plasma
Plasma Regeneration
Plasma, the liquid portion of your blood, makes up about 55% of your total blood volume, while the blood cell portion comprises about 45%.Your plasma is composed mainly of water, and it also contains minerals, proteins, and hormones.
Sometimes, when blood is collected from the body, the plasma is machine-separated from blood cells as part of certain medical procedures or for donation. When it’s isolated, plasma looks like a straw-colored, cloudy liquid.
Find out what blood plasma is and how it’s involved in a blood transfusion or other procedures.
Role and Composition of Plasma in the Body
Your blood flows through your heart and the blood vessels throughout your body. Whole blood appears red because of its red blood cells. Without the blood cells, the remaining plasma is straw-colored and slightly cloudy.
Because of its liquid plasma content, whole blood moves as a fluid through yourheart, arteries, veins, and capillaries. As your heart pumps, blood circulates to all your organs, tissues, and cells, providing oxygen, nutrients (such as glucose), hormones, immune proteins, vitamins, and minerals.
Major components of blood plasma include:
Blood is filtered in the kidneys, where waste material is removed from plasma for excretion from the body. Additionally, your kidneys adjust your blood mineral and fluid concentration, maintaining an optimal total amount and ratio of these plasma components. The kidneys send excess water and minerals to the urine for release from the body.
Your blood plasma fluid volume and mineral concentration are balanced to keep you hydrated and your organs and cells functioning properly.
Plasma vs. SerumWhen blood clots, the liquid portion is now called serum. Serum lacks certain proteins and other elements used in the clotting process.When plasma is necessary for a blood test (such ascoagulation tests), the collection tube contains chemicals that prevent the blood from clotting in the tube.
Plasma vs. Serum
When blood clots, the liquid portion is now called serum. Serum lacks certain proteins and other elements used in the clotting process.When plasma is necessary for a blood test (such ascoagulation tests), the collection tube contains chemicals that prevent the blood from clotting in the tube.
For Recipients
If you have rapidly lost fluid, you may experience serious health effects.A severe fluid deficit leads to low blood pressure, brain damage, disruption of kidney function, and heart failure. Severe fluid loss can also harm other areas of the body, such as the intestines, liver, and lungs.
A plasma transfusion can restore the fluid and other components of plasma to prevent these consequences and maintain healthy, functioning cells throughout the body.
Donated plasma can also function as a supply of therapeutic biological materials, such as immune proteins and certain hormones, and in the manufacture of medications.
Donor Benefits
Some evidence suggests that donating plasma may benefit people withhigh cholesterolor high blood pressure. A study examining these potential effects is currently underway.
Plasma DonationBefore you donate blood or plasma, you would have blood typing andscreening tests.You can’t donate blood if you have anemia (red blood cell deficiency). You also can’t donate plasma if you have a blood disorder or certain infections, such as HIV and hepatitis.During a plasma donation, a phlebotomist (a person specially trained to draw blood) inserts a line into a vein. Your blood travels through a machine that separates plasma from the cellular components of your blood. The cellular components are returned to your vein.
Plasma Donation
Before you donate blood or plasma, you would have blood typing andscreening tests.You can’t donate blood if you have anemia (red blood cell deficiency). You also can’t donate plasma if you have a blood disorder or certain infections, such as HIV and hepatitis.During a plasma donation, a phlebotomist (a person specially trained to draw blood) inserts a line into a vein. Your blood travels through a machine that separates plasma from the cellular components of your blood. The cellular components are returned to your vein.
Before you donate blood or plasma, you would have blood typing andscreening tests.You can’t donate blood if you have anemia (red blood cell deficiency). You also can’t donate plasma if you have a blood disorder or certain infections, such as HIV and hepatitis.
During a plasma donation, a phlebotomist (a person specially trained to draw blood) inserts a line into a vein. Your blood travels through a machine that separates plasma from the cellular components of your blood. The cellular components are returned to your vein.
Difference Between Blood Donation and Plasma Donation
If you’re giving a blood donation, you can donate blood or plasma. It takes a little longer to donate plasma than it takes to donate whole blood. Whole blood donation may take an hour.
During a plasma donation, sometimes calledplasmapheresis, a tube is inserted into your vein, and blood passes through a machine to separate only the plasma portion.The red cells, white cells, and platelets are returned to your bloodstream.
With a whole blood donation, no cells are returned to you. The donated whole blood unit may be processed into components, such as packed red cells and plasma. These can then benefit more than one recipient.
You candonate plasma more frequently than whole bloodbecause the body regenerates plasma much faster than it regenerates blood cells.
Depending on your ABO blood type, your plasma may contain immune proteins (antibodies) that react with incompatible red blood cells (atransfusion reaction). Blood type AB plasma has no antibodies for types A or B and can go to any recipient, so it is the most desired plasma donation for transfusion.
This differs from whole blood or packed red blood cell donation, where type O is more desired because the cells lack A or B antigens and can go to people of any blood type.However, people of all blood types are encouraged to donate whole blood and plasma because of the need for all types.
Plasma donors may be paid for their donations at for-profit plasma centers. When plasma is collected from paid donors, it is used for purposes other than direct transfusion.Payment is not usually given for whole blood donations for transfusions in the United States.
Therapeutic PlasmapheresisTherapeutic plasmapheresis removes certain components from plasma and then returns the plasma back to the body. This process may treat immune disorders, which occur when the immune system damages the body’s organs.Examples of immune disorders that therapeutic plasmapheresis may treat includeGuillain-Barré syndrome,myasthenia gravis, and multiple sclerosis.
Therapeutic Plasmapheresis
Therapeutic plasmapheresis removes certain components from plasma and then returns the plasma back to the body. This process may treat immune disorders, which occur when the immune system damages the body’s organs.Examples of immune disorders that therapeutic plasmapheresis may treat includeGuillain-Barré syndrome,myasthenia gravis, and multiple sclerosis.
Special equipment separates plasma from blood cells or selected proteins from plasma. Though the process runs continuously for an hour or longer, only a small amount of blood passes through the machine at a time. Your blood cells and saline are returned to your bloodstream.
If you’re having therapeutic plasmapheresis, you would have a tube placed in a vein. As the blood runs through the tube, it enters a machine that separatesantibodies(specialized immune proteins) or other materials from your plasma before returning the plasma and blood cells to your body.
Plasma Regeneration After Donation
You may feel tired for a few days after you donate blood or plasma. This is due to mild anemia and dehydration from the procedure.It’s important to get some rest after your procedure and as you recover.
After plasma donation, it’s important to drink fluids, especially water. It’s good to have a small meal soon after the donation.
If you are healthy, your body will replace the lost plasma fairly quickly after a plasma donation or whole blood donation.If you are drinking enough fluids, your blood volume will be restored in 48 hours.However, when you donate whole blood, it takes the body longer to replace red blood cells.
Side Effects of Plasma DonationIf you feel dizzier or more tired than expected or if you remain tired or dizzy for more than a few days after donating blood or plasma, call or see a healthcare provider.
Side Effects of Plasma Donation
If you feel dizzier or more tired than expected or if you remain tired or dizzy for more than a few days after donating blood or plasma, call or see a healthcare provider.
Summary
Plasma is the liquid portion of your blood, making up more than half of your blood volume. Your kidneys adjust the composition of plasma to keep your body’s function in balance. You may need to receive a plasma transfusion if you have rapid fluid loss, such as due to a severe burn or major traumatic injury.
Plasmapheresis is a procedure that can treat certain immune diseases. You may feel tired after donating blood or plasma or after having a therapeutic plasmapheresis treatment. Make sure to ask about instructions and follow guidance regarding hydration, diet, medication, and rest after any of these procedures to speed up your recovery.
Why Do People Need Blood Transfusions?
13 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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