Antithrombogenic Additive Prevents Dialysis Blood Clotting

A new hemodialysis system uses surface-modifying macromolecules to prevent the formation of blood clots, obviating the use of blood thinners.

Under development by Fresenius Medical Care North America (Fresenius; Waltham, MA, USA), the new hemodialysis system will integrate the Evonik Healthcare (Essen, Germany) Endexo fluoro-oligomeric additive--an innovative polymer that inhibits adsorption of protein and platelets--into the manufacturing process of dialyzers and bloodlines. The low molecular weight, antithrombogenic additives migrate to the top few nanometers of the device surface during the manufacturing process, providing passive surface modification.

In the presence of blood, the modified surfaces are able to suppress procoagulant protein conformation, reduce platelet adhesion, reduce deep vein thrombosis (DVT) by 50%, and reduce tissue plasminogen activator (tPA) triggering in platelets by 59%. In the presence of bacteria mediated fluids, the modified surfaces are effective at reducing bacteria adhesion (up to 5 log CFU), encrustation, and biofouling. The Endexo platform technology can be applied to most base polymers (polyurethane, polysulfone, PVC, polypropylene, and silicone) and manufacturing techniques (such as extrusion, solution spinning, and injection molding).

“Many dialysis patients are currently prescribed blood thinners, like heparin, to reduce the risk of clotting as blood travels from their body, through bloodlines, and into the dialyzers that filter out toxins,” said Olaf Schermeier, CEO for global research and development at Fresenius. “Harnessing our innovational expertise, we continuously strive to make significant advances in our products and provide new solutions for people with chronic kidney disease worldwide.”

Hemodialysis requires some form of anticoagulation, usually with heparin, to prevent thrombosis in the blood circuit. This consists of a dose of heparin given as a bolus at the start of the dialysis treatment, with a mid-treatment dose to maintain suitable anticoagulation. Alternatively, heparin modeling can be performed using an initial bolus, followed by a constant fixed infusion of heparin to maintain activated clotting time. Regional anticoagulation with citrate, prostacyclin, and heparin-protamine has also been used.

Related Links:
Fresenius Medical Care North America
Evonik Healthcare