Therapeutic Plasma Exchange (Therapeutic plasma exchange) is a medical procedure that separates plasma from blood cells (plasma is the lymph fluid that we commonly understand) to remove antibodies or other pathogenic substances present in the plasma. Blood is drawn from the body through a needle inserted in the arm (one line for drawing blood out and another line for returning blood at the same time) or through a large central venous catheter.
The removed plasma is replaced with a colloid fluid which is generally albumin, saline, or fresh frozen plasma (FFP)
Purpose of Therapeutic Plasma Exchange
Therapeutic plasma exchange has multiple purposes as a treatment to remove plasma components in the blood that contain pathogenic substances in various conditions including neurological diseases, hematology, metabolism, rheumatoid diseases, and kidney diseases as well as poisoning conditions.
According to the recommendation of the American Society for Apheresis (ASFA) 2023, indications are classified into 4 groups: Group I to IV based on available medical data. Here, Group 1 is referenced due to clear beneficial data, as follows:
1. Neurological diseases
- Guillain-Barre syndrome
- Myasthenia gravis (MG) (for acute short-term treatment)
- Chronic inflammatory demyelinating polyneuropathy
- N-methyl-D-aspartate receptor antibody encephalitis
2. Hematological diseases
- Hyperviscosity in hypergammaglobulinemia
- Thrombotic microangiopathy, complement mediated (antibody against factor H)
3. Kidney diseases
- Goodpasture syndrome (except in cases where dialysis is required and there is no pulmonary alveolar hemorrhage)
- AAV nephritis with pulmonary alveolar hemorrhage
4. Related to organ transplantation
- Treatment and preparation for kidney, liver, or lung transplantation to reduce the chance of tissue rejection
5. Other diseases
- Fulminant Wilson disease
- Severe liver failure when indicated
Contraindications and Precautions
- Unable to insert a venous catheter
- Sepsis or unstable blood pressure
- Allergy to fresh frozen plasma (FFP) or albumin
- Allergy to heparin, a commonly used anticoagulant
- Hypocalcemia
Steps of Therapeutic Plasma Exchange
Step 1 The doctor assesses venous access. Patients with suitable veins will have needles inserted in each arm, while patients with unsuitable veins will have a central venous catheter inserted before treatment.
Step 2 Connect the venous catheter to the plasmapheresis machine. This machine draws blood into a cell separator centrifuge which separates plasma from blood according to the volume specified by the doctor. The plasma containing pathogenic substances is then removed and collected in a waste bag.
Step 3 Replacement fluids (albumin, saline, or FFP) are added to the remaining red blood cells and platelets in the machine. Then, the entire new blood is returned to the body through the venous catheter on the other side.
Step 4 The process of drawing blood out and returning it is automatic and continuous to minimize blood loss and help maintain fluid balance in the body.
Step 5 The treatment generally takes 1-2 hours.
Risks and Possible Side Effects?
Therapeutic plasma exchange is a safe treatment but side effects may occur such as discomfort at the needle insertion site, fatigue, and dizziness.
The most common side effect is feeling cold. In this case, heating pads, blood warmers, and blankets are used to help keep you warm and comfortable. It is important to inform the nurse immediately if these symptoms begin.
Less common side effects include electrolyte imbalances, decreased platelets and clotting factors, or allergic reactions to FFP or Albumin. Therefore, close hospital monitoring is necessary.
After Therapeutic Plasma Exchange Treatment
- Drink enough water continuously for at least 24 hours
- Eat sufficiently.
- Minimize physical activity for several hours after treatment
- Observe the venous catheter site for any bleeding.
Therapeutic plasma exchange (Therapeutic Plasma Exchange) is an important medical procedure that can effectively treat diseases caused by immune system and plasma protein abnormalities. Although there are some precautions and side effects, overall it is considered safe when performed in a hospital under the care of a specialized medical team.
Dr. Methinee Sutthiwaikit
Nephrology Specialist
Phyathai 2 Hospital
