Plasma, a light yellow liquid, forms a significant part of human blood, transporting numerous substances throughout the body. Beyond its natural role, plasma is a versatile component in modern medicine, offering direct therapeutic applications and serving as the source for many life-saving medications.
What is Blood Plasma?
Blood plasma constitutes about 55% of total blood volume, composed primarily of water (approximately 92%). This watery solution carries a complex mixture of dissolved substances, including proteins, salts, hormones, nutrients, and waste products. Plasma appears as a pale, straw-colored fluid.
Proteins such as albumin, globulins, and fibrinogen make up about 7% of plasma’s volume. Albumin helps maintain osmotic balance within blood vessels, preventing excessive fluid leakage into tissues, and acts as a carrier for various molecules. Globulins include antibodies that help the immune system fight infections, and fibrinogen is crucial for blood clot formation. Electrolytes like sodium, potassium, chloride, and bicarbonate also help maintain the body’s pH balance.
Direct Medical Uses of Plasma
Direct medical uses of plasma primarily involve transfusions of fresh frozen plasma (FFP). This plasma is processed and frozen quickly after donation to preserve its beneficial proteins. FFP transfusions are often given to replace missing or low levels of blood proteins.
Such transfusions are particularly important in severe bleeding, where they help restore blood volume and provide clotting factors to stop hemorrhage. Patients with liver disease, whose livers may not produce enough clotting proteins, also benefit from plasma transfusions to manage bleeding complications. Plasma transfusions are used for individuals experiencing severe burns, shock, or trauma, as they help increase blood volume and prevent shock.
Life-Saving Plasma-Derived Medications
Plasma is also a source for numerous medications, produced through a process called plasma fractionation. This involves separating plasma into its individual protein components using techniques like precipitation, centrifugation, and filtration, often employing cold ethanol. Each isolated protein can then be purified and concentrated to create therapies targeting specific medical conditions.
Immunoglobulins, also known as antibodies, are proteins extracted from plasma. These medications treat various immune deficiencies, where the body cannot produce enough of its own antibodies to fight infections. They are also used in managing autoimmune diseases, such as Guillain-Barre syndrome, myasthenia gravis, and lupus, by modulating the body’s immune response. Immunoglobulin therapy can also address certain infections and conditions like Kawasaki disease.
Albumin is the most abundant protein in plasma and is used in several medical scenarios. It is administered to patients suffering from shock, severe burns, and liver or kidney disease to help maintain blood volume and prevent fluid from leaking out of blood vessels. Albumin infusions can also address hypovolemia (low blood volume) and restore protein balance in patients recovering from surgery.
Clotting factors are essential for proper blood coagulation. Concentrates of these factors are used to treat bleeding disorders like hemophilia, where patients lack specific proteins needed for clotting. They are also used for other conditions such as von Willebrand disease and antithrombin III deficiency. In some instances, such as Factor V deficiency, plasma transfusion may be indicated when specific factor concentrates are unavailable.
Alpha-1 antitrypsin is a plasma protein that helps protect the lungs from damage. Medications derived from this protein are used to treat individuals with Alpha-1 antitrypsin deficiency, a genetic condition that can lead to severe lung diseases, including emphysema. These treatments help to supplement the deficient protein, thereby reducing lung tissue breakdown.
C1-esterase inhibitor is another plasma-derived product used to manage hereditary angioedema (HAE). HAE is a rare genetic disorder characterized by recurrent episodes of severe swelling in various parts of the body, including the face, airways, and intestines. C1-esterase inhibitor medications help to prevent and treat these swelling attacks by supplementing the deficient protein that normally helps control inflammation.
The Role of Plasma Donation
Plasma donation is a process called plasmapheresis, where blood is drawn from a donor, and a machine separates the plasma from the other blood components. The red blood cells, white blood cells, and platelets are then returned to the donor’s body, along with some saline. This method allows individuals to donate plasma more frequently than whole blood, typically up to twice within a seven-day period.
Plasma donors undergo thorough health screenings, including medical exams and tests for infectious diseases, to ensure donor and recipient safety. Donation centers follow strict hygiene protocols, using sterile, single-use equipment to prevent contamination. This rigorous screening and collection process makes plasma donation a safe procedure for eligible individuals.
The continuous need for plasma donations is significant, as plasma is the raw material for all the life-saving therapies and medications mentioned. Donors play a direct role in providing treatments for patients with immune deficiencies, bleeding disorders, severe burns, and other serious medical conditions. Without a steady supply, the production of these essential therapies would not be possible.