What is Blood Plasma, Functions, Importance, and Uses in Modern Medicine

Blood plasma is a vital part of human blood. It plays a crucial role in maintaining overall health. Plasma also supports various medical treatments. It comprises about 55% of total blood volume.

It is the pale yellow, straw-colored liquid that remains after red blood cells, white blood cells, and platelets are removed.

Plasma consists of proteins, enzymes, and electrolytes. Plasma serves as a transport medium. It is a key player in many physiological functions.

Composition of Blood Plasma

Blood plasma is made up of approximately 90% water and 10% dissolved substances, including:

• Plasma proteins (albumin, globulins, fibrinogen)
• Electrolytes (sodium, potassium, calcium, chloride)
• Hormones
• Nutrients (glucose, amino acids, fatty acids)
• Waste products (urea, carbon dioxide)

Functions of Blood Plasma

Plasma performs several essential functions in the body:

1. Transport of nutrients and hormones – Plasma carries vital substances such as glucose, vitamins, and hormones to tissues and organs.
2. Waste removal – It transports waste products to the liver, kidneys, and lungs for excretion.
3. Blood clotting – Holds clotting factors like fibrinogen to prevent excessive bleeding.
4. Immunity support – Globulin’s in plasma act as antibodies, helping fight infections.
5. Maintaining blood pressure and volume – Albumin helps regulate oncotic pressure, keeping fluid in blood vessels.

Importance of Plasma in Medicine

Blood plasma is not just critical within the human body—it also has significant therapeutic and diagnostic applications:

1. Plasma Donation and Transfusions

Donated plasma is used to treat:

• Burn victims
• Trauma and shock patients
• Liver disease
• Clotting disorders like hemophilia

Plasma donation is safe, and donated plasma can be frozen (FFP – Fresh Frozen Plasma) for future use.

2. Plasma-Derived Therapies

Plasma proteins are extracted to create life-saving medications, such as:

• Immunoglobulins – for immune deficiencies and autoimmune diseases
• Clotting factors – for hemophilia patients
• Albumin – for liver disease and surgical shock

3. Diagnostic Uses

Plasma tests are used in clinical diagnostics to measure:

• Blood sugar levels
• Cholesterol
• Hormone levels
• Electrolyte balance

Who Can Donate Plasma?

To donate plasma, individuals typically must:

• Be 18–65 years old
• Weigh at least 110 pounds (50 kg)
• Pass a health screening and medical history check

NOTE: Plasma can be donated more frequently than whole blood, usually twice per week.

Plasma Storage and Shelf Life

Once collected, plasma can be stored for extended periods depending on how it is processed:

• Fresh Frozen Plasma (FFP) – Stored at -18°C or colder, it can last for up to one year.
• Liquid Plasma – Stored at 1–6°C and typically used within 5 days of collection.

Proper storage ensures plasma retains its therapeutic properties. This makes it ready for use in emergency medicine, surgery, and chronic disease treatment.

How to Collect Plasma in a Hematology Laboratory

Plasma collection in a hematology laboratory is a carefully controlled process that ensures purity and safety. Here’s a general overview:

1. Blood Collection: Whole blood is drawn from a vein. A sterile syringe or collection bag containing anticoagulant is used. The anticoagulant, usually EDTA or citrate, prevents clotting.
2. Centrifugation: The blood sample is placed in a centrifuge and spun at high speed (typically 1000–2000g for 10–15 minutes). This separates the blood into layers:
   • Top layer: Plasma
   • Middle layer: Buffy coat (white cells and platelets)
   • Bottom layer: Red blood cells
3. Plasma Extraction: A sterile pipette or automated system is used. The plasma (top layer) is extracted carefully. This avoids disturbing the other layers.
4. Labeling and Storage: The extracted plasma is labeled with patient or donor information, date, and time. It is then stored at appropriate temperatures depending on its intended use.
5. Quality Control: Some labs conduct further tests to check for contamination. They also measure protein levels. These tests help identify disease markers before the plasma is used for analysis or therapy.

Conclusion

Blood plasma is an indispensable part of human health and modern medicine. It can transport substances and aid in clotting. It also supports immune functions. These abilities make it essential not just in the body but also in life-saving treatments for others. Whether you’re interested in understanding your health, or you are considering donating, it’s important to know the role of plasma. This knowledge helps you appreciate just how vital this golden fluid truly is.