[Plasma exchange by cascade filtration. Clinical and biological study]

Area of Science:

• Nephrology
• Immunology
• Biomedical Engineering

Context:

• Plasma exchange is a therapeutic apheresis technique used to remove harmful substances from blood.
• Double-filtration plasmapheresis (DFPP) is an advanced apheresis method employing two filters with distinct pore sizes.
• DFPP aims to selectively remove pathological plasma components while minimizing the loss of beneficial ones.

Purpose:

• To evaluate the efficacy and selectivity of a double-filtration plasmapheresis system in patients with various risk factors.
• To assess the performance of the two-filter system in separating plasma components and its potential for therapeutic applications.
• To compare the efficiency and plasma substitute requirements of DFPP with conventional methods.

Summary:

• Nineteen DFPP sessions were conducted in 8 patients, utilizing a system with a plasma separator and a plasma filter.
• The system modulates pressures, recirculates plasma, and quantifies extracted plasma mass, with antihistamines administered and vital signs monitored.
• The second filter demonstrated good selectivity for high (IgM) and low (albumin) molecular weight components but requires improvement for intermediate molecules (IgG, immune complexes).

Impact:

• DFPP significantly reduces plasma substitute usage compared to conventional methods (approximately 6-fold reduction).
• The technique is potentially beneficial for diseases mediated by high molecular weight substances.
• Further optimization is needed to improve transmembrane pressure control and enhance selectivity for intermediate molecular weight components, particularly IgG, for broader clinical application.