What is plasmapheresis (plasma exchange)?

From the Guidelines

Plasmapheresis should be considered as a treatment option for patients with severe autoimmune disorders, such as myasthenia gravis, Guillain-Barré syndrome, and thrombotic thrombocytopenic purpura, as it can rapidly reduce circulating antibodies and immune complexes, providing immediate relief while other immunosuppressive therapies have time to take effect. The procedure involves removing plasma from the blood to eliminate harmful substances circulating in the bloodstream, and a typical treatment regimen involves 4-6 sessions over 1-2 weeks, with each session lasting 2-4 hours and processing 1-1.5 times the patient's plasma volume 1. Common side effects include hypotension, fatigue, nausea, and potential allergic reactions to replacement fluids, and patients should maintain adequate hydration before treatment and inform their healthcare provider about all medications they're taking, as plasmapheresis can remove certain drugs from the bloodstream. Some key considerations for the use of plasmapheresis include:

• The timing of rituximab infusion in relationship to plasmapheresis needs to be considered, as plasmapheresis can remove rituximab 1
• Plasmapheresis can be associated with hemodynamic shifts, coagulation disorders, electrolyte imbalances, and line-related bacteremia, and requires a careful risk-benefit analysis 1
• The use of plasmapheresis in non-HBV-associated polyarteritis nodosa is not recommended, except in catastrophic cases unresponsive to aggressive immunosuppressive therapies 1
• Vascular access is typically established through a central venous catheter for short-term treatment or an arteriovenous fistula for long-term therapy. Overall, plasmapheresis can be a valuable treatment option for patients with severe autoimmune disorders, but its use should be carefully considered and monitored to minimize potential risks and maximize benefits.

From the Research

Indications for Plasmapheresis

• Plasmapheresis has been used in the management of immunologic renal disease for the last 40 years, with the rationale of removing pathogenic immune mediators from the circulation 2.
• It is used in renal transplantation for the treatment of acute antibody-mediated rejection, and for desensitization of patients with preformed anti-HLA antibodies or those receiving an ABO-incompatible transplant 2.
• Plasmapheresis appears to be of benefit in patients with Guillain-Barré syndrome of recent onset, particularly those who receive treatment within 7 days of onset and those who require mechanical ventilation 3.
• It is also used to treat neurological, renal, hematological, and systemic diseases, including myasthenia gravis, glomerulonephritis, refractory systemic lupus erythematosus, cryoglobulinemia, and immune cytopenic disorders 4, 5.

Mechanisms of Action

• Plasmapheresis works by removing pathogenic antibodies and immune complexes from the circulation, which can contribute to disease pathogenesis 2, 4.
• It can also deplete proinflammatory molecules, such as complement components and coagulation factors, which can contribute to inflammation and tissue damage 2.
• Repeated intensive plasmapheresis can achieve significant depletion of immunoglobulins and immune complexes, but sustained depletion requires concomitant immunosuppressive therapy 4.

Techniques and Complications

• Plasmapheresis has evolved into a frequently used, relatively safe procedure, with a large spectrum of different techniques existing, each with its own possible complications 5.
• The technique involves the removal of pathogenic macromolecules from the plasma using an extracorporeal method 5.
• Complications can occur, but the procedure is generally considered safe when performed by experienced professionals 5.

Current Knowledge and Unanswered Questions

• Apheresis, including plasmapheresis, can remove pathogens and mediators that contribute to pathogenic inflammatory responses in diseases not generally considered to be "Hematologic" 6.
• The clinical efficacy and pathophysiologic changes that occur during apheresis in these conditions are largely unknown, and research in these areas has the potential to benefit many patients with a variety of diseases 6.