Extracorporeal and Filtration Medical Textiles

Extracorporeal medical textiles function outside the human body in contact with blood or other body fluids for dialysis, oxygenation, plasma filtration, and haemoperfusion. Haemodialysis membranes use hollow fibre technology: polysulfone (PS) or polyethersulfone (PES) hollow fibres (inner diameter 180–200 µm, wall thickness 30–50 µm, pore size 5–30 nm) spun by dry-wet spinning at 3,000–15,000 fibres per dialyser module achieving membrane surface area of 1.0–2.1 m². Urea clearance of 200–250 mL/min and beta-2 microglobulin clearance of 50–100 mL/min define high-flux performance (ISO 8637-1). Blood oxygenator membranes (microporous PP hollow fibres, inner diameter 200–400 µm, porosity 40–50%, pore size 0.03–0.1 µm) transfer O₂ at 200–350 mL/min and remove CO₂ at 150–250 mL/min during cardiopulmonary bypass at blood flow rates of 3–6 L/min. Biocompatibility requirements (ISO 10993-4 haemocompatibility) mandate platelet activation <20% and haemolysis index <0.1% NIH. Heparin-coated surfaces (1–3 µg/cm²) reduce thrombosis on extracorporeal circuits. Global extracorporeal device market exceeds $4.2 billion, with 2.5 million haemodialysis patients worldwide requiring 156 million dialyser units/year.