Plasma is the largest single component of blood. It consists of water, vital proteins, and other substances that play a role in coagulation, immunity, blood pressure, and transporting nutrients.

Scientists can separate blood into four main components:

Roughly 55% of blood is plasma, with the other three components making up the other 45%. As plasma is the liquid portion of blood, it plays a vital role in many bodily systems as it facilitates the transportation of important substances around the body.

In this article, we discuss the functions of plasma, how it keeps the body healthy, and the importance of donating plasma.

An image of blood in a centrifuge, which separates the plasma from other blood components.Share on Pinterest

Plasma, also known as blood plasma, is the straw-colored liquid part of blood. It is the largest single component of blood, making up roughly 55%.

Plasma itself consists of 92% water. Vital proteins involved in many functions such as blood clotting, fighting infections, and transporting substances make up 7% of plasma. The remaining 1% contains mineral salts, sugars, fats, hormones, and vitamins.

As plasma forms the liquid base of blood, it serves many functions in the body. Some of these functions include:

  • Coagulation: Many important proteins, such as fibrinogen, thrombin, and factor X, are present in plasma and play a vital role in the clotting process to stop a person from bleeding.
  • Immunity: Blood plasma contains disease-fighting proteins, such as antibodies and immunoglobulins, which play a crucial role in the immune system by fighting pathogens.
  • Blood pressure and volume maintenance: A protein present in plasma called albumin helps to maintain the oncotic pressure. This prevents fluid from leaking into areas of the body and skin where less fluid usually collects. This also helps ensure blood flow through blood vessels.
  • pH balance: Substances present in blood plasma act as buffers, allowing plasma to maintain a pH within normal ranges, which helps to support cell function.
  • Transportation: Plasma in the blood helps to transport nutrients, electrolytes, hormones, and other important substances throughout the body. It also helps to remove waste products by transporting them to the liver, lungs, kidneys, or skin.
  • Body temperature: Plasma helps maintain body temperature by balancing heat loss and heat gain in the body.

By performing the above functions, plasma helps to keep people healthy. It ensures that nutrients, hormones, proteins, and other substances get to the part of the body that requires them.

As it is such a vital component of blood, it also plays a critical role in the treatment of many serious health problems.

Plasma contains many important substances, namely antibodies, clotting factors, and proteins such as albumin and fibrinogen. This is why there are blood drives asking people to donate plasma. After collecting donated plasma, healthcare professionals freeze it to preserve its quality and function. They refer to this as fresh frozen plasma, or FFP.

They can then issue FFP to hospitals or pharmaceutical companies that can further process, separate, and concentrate the vital substances present in the plasma into various products that doctors can use as lifesaving treatments.

For example, from FFP, scientists can prepare cryoprecipitate, which is rich in clotting factors and can help people with bleeding disorders.

Blood and its components are a precious resource in healthcare. Evidence notes that the healthcare system in the United States requires nearly 10,000 units of plasma every day. For this reason, some people refer to blood plasma as liquid gold.

Clinically, healthcare professionals can use plasma in various ways. In particular, plasma can be part of lifesaving treatments for people who have trauma and burn injuries or those with severe liver diseases and rare blood diseases.

Blood donation is a safe and simple procedure where a person donates blood products. People can donate plasma through either whole blood or plasma donations.

With whole blood donations, a person donates all the components of blood. Healthcare professionals can give whole blood to those who may need it, such as those recovering from surgery, or scientists can separate the blood into different components and use them as needed.

Plasma donation involves drawing blood, extracting the plasma, and returning the rest of the blood to the donor through a process called plasmapheresis. This type of donation takes slightly longer than whole blood, but as a person is only donating plasma, it yields a larger volume of blood plasma, meaning people can donate more frequently.

People with AB blood type have a universal type of plasma, which means that anyone can receive this plasma safely. People in emergency situations can receive this type of plasma immediately, which could mean the difference between life and death.

The American Red Cross urge people with type AB blood to donate plasma. People with this blood type can do this every 28 days, or up to 13 times a year.

Click here to learn more about donating plasma.

Plasma is the yellow-colored, liquid component that makes up most of the blood. It helps with immunity, blood clotting, maintaining blood pressure, blood volume, and pH balance in the body. It also plays a key role in transporting blood cells, nutrients, proteins, waste products, and hormones throughout the body.

People who are capable of donating blood may want to consider donating plasma. It is in high demand as it can be very useful for treating people with massive blood loss, liver failure, cancer, rare diseases, or other health issues.

If an individual wants to donate blood or plasma, they can find their nearest center using the AABB’s Blood and Convalescent Plasma Donation Site Locator. Alternatively, people can find a donation drive through the American Red Cross.