Plasma is composed of 91%-92% of water and 8%-9% of solids. It mainly contains coagulants (mainly fibrinogen which aid in blood clotting), plasma proteins (such as albumin and globulin that help sustain the colloidal osmotic pressure at approximately 25 mmHg), electrolytes (like sodium, potassium, and calcium that help maintain blood pH level), and immunoglobulins (which help counter infection and other small amounts of enzymes, hormones, and vitamins).

What is plasma?

Plasma, also known as blood plasma, looks light-yellowish or straw-colored. It is the liquid base for whole blood. Whole blood minus erythrocytes (RBCs), leukocytes (WBCs), and thrombocytes (platelets) forms the plasma.

The origin of plasma, which accounts for 55% of total blood, is not produced by any organ but is formed from water and salts absorbed by the digestive tract.

What does plasma do for the body?

As plasma serves the liquid base of blood, the functions provided by plasma and blood overlap. The collective functions include: 

  • Coagulation: fibrinogen has a major role in blood clotting along with other procoagulants, like thrombin and factor X.
  • Defense: immunoglobulins and antibodies in plasma assist the body’s defense against bacteria, viruses, fungi, and parasites.
  • Maintenance of Osmotic Pressure: the colloidal osmotic pressure is leveled at around 25 mmHg by the plasma proteins, like albumin synthesized by the liver.
  • Nutrition: transfer of nutrients like glucose, amino acids, lipids, and vitamins absorbed through the digestive tract to different areas of the body act as a main source of fuel for growth and development.
  • Respiration: transportation of respiratory gases, i.e., transferring oxygen to various organs and bringing carbon dioxide back to the lungs for excretion.
  • Excretion: the blood eliminates nitrogenous waste products that were produced after cellular metabolism and carries them to the kidney, lungs, and skin for excretion.
  • Hormones: the blood carries hormones to the organs they are intended to affect.
  • Regulation of Acid-Base Balance: plasma proteins contribute to acid-base balance through their buffering function.
  • Regulation of Body Temperature: maintained by balancing heat loss and heat gain in the body.
  • Role in Erythrocyte Sedimentation Rate (ESR): fibrinogen, an acute phase reactant, elevates during acute inflammatory conditions and helps with the increase in ESR, which is used as diagnostic and prognostic equipment.

Which plasma constituent is the main contributor to clotting?

There are four major products that are derived from the plasma and can be used:

  • fresh-frozen plasma (FFP)
  • plasma is frozen within 24 hours of phlebotomy (FP24)
  • cryoprecipitate-poor plasma (CPP), and thawed plasma.

It should be noted that FP24, CPP, and thawed plasma contain varying amounts of clotting factors.

The lack of specific clotting factors causes hemophilia. Hemophilia A is caused by factor VIII deficiency, while hemophilia B is due to insufficiency of factor IX. Symptoms involve hemarthrosis and intramuscular hematomas. Prophylactic transfusion of a factor VIII or factor IX concentrate is the main treatment used for children with severe hemophilia; however, this leads to the formation of antibodies against these factors over time.

How often can you donate plasma?

If you want to donate plasma, it can be as often as every two weeks. Blood donation is usually done every 12 weeks for men and 16 weeks for women. Typically, the heavier a donor is, the more plasma can usually be collected and the longer the appointment takes. At most donation centers, compensation for an appointment is typically between $50 and $75. First-time donors could receive big bonuses, too.

Blood plasma is initially tested to ensure its safety for transfusion. According to the FDA regulations, the blood plasma undergoes a battery test to identify transmittable diseases, mainly hepatitis A, hepatitis B, and hepatitis C, along with syphilis and HIV. Fractionation separates individual plasma proteins into different fractions. 

After getting a tattoo, giving blood can be dangerous. Though uncommon, a dirty tattoo needle can carry a variety of bloodborne viruses, including hepatitis B.

Plasma can be separated out of whole blood by spinning it with an anticoagulant in a centrifuge. Blood plasma is lighter than red blood cells, which form the lower yellowish layer. Plasma is frozen within 24 hours so that it can be used for transfusions without losing its functionality. It is thawed before use and has a shelf life of up to one year. While type O blood is the most desirable preference for blood for transfusions, the plasma of AB types is the most preferred because its plasma does not contain antibodies which could cause an adverse reaction.

Plasma donations are used for slightly different purposes than general blood donations. Plasma donation is used for individuals who have experienced trauma, burns, or shock; adults or children with cancer; and people with liver or coagulation disorders.

What is the difference between serum and plasma?

The distinguishing factor between plasma and serum is that plasma has fibrinogen which is absent in serum.

Both plasma and serum can come from blood using a centrifuge, but it should be noted that serum is obtained after the clotting of blood, while plasma can be drawn out before the coagulation of the blood.

Serum is commonly used for blood typing but can also be used for diagnostic testing. Plasma, on the other hand, is known to be used for blood-clotting-related problems.

Which hormone works directly in the intestine to increase plasma calcium levels?

Calcitonin is a hormone that the thyroid gland creates and releases to help regulate calcium levels in the blood by decreasing it. Calcitonin counteracts the functions of the parathyroid hormone, which is a hormone that elevates blood calcium levels. Both parathyroid hormone and calcitonin help manage the level of calcium in your blood, which is important for a number of significant bodily functions. The difference is how they do so and how much they influence your calcium levels.

What are plasma proteins?

Distinct organs produce plasma proteins based on an individual’s stage of development. 

For instance, mesenchymal cells produce plasma cells during the embryonic period. Albumin is the first protein to be created, followed by globulin and the rest of the plasma proteins.

In addition, adult plasma protein synthesis is carried out by the liver’s reticuloendothelial cells. Plasma protein structure is further influenced by the bone marrow, spleen, aging blood cells, and general body tissue cells. B lymphocytes produce immunoglobulins, which in turn produce gamma globulins.