Antithrombotic properties of hemofilter coated with polymer having a hydrophilic blood

Extracorporeal circulation devices are coated with a biocompatible polymer coating agent (BPCA) that has a hydrophilic blood-contacting layer, but hemofilters are not. We aimed to investigate the antithrombotic properties of a BPCA-coated hemofilter. Four experiments using BPCA-coated circuits and non-coated hemofilters and four experiments using BPCA-coated circuits and BPCA-coated hemofilters were performed with whole human blood and compared by measuring the circuit pressure every 5？min, antithrombin activity every 40？min, and thrombin–antithrombin complex every 40？min, for a total of 240？min of recirculation. The mean time required for the pressure at the inlet of the hemofilter to increase sharply was longer in BPCA-coated than in non-coated hemofilters (66？±？11？min vs 25？±？9？min, p？<？0.01). The mean antithrombin activity value at 200 and 240？min of recirculation was significantly higher in the experiments with BPCA-coated versus non-coated hemofilters (43.3？±？2.87 vs 33.3？±？5.74, p？=？0.04; 42.8？±？3.59 vs 31.0？±？5.35, p？=？0.01, respectively); the antithrombin activity values at the other time points were not significantly different. Furthermore, all thrombin–antithrombin complex values in experiments with the BPCA-coated hemofilters achieved overrange at 80？min of recirculation, whereas those with the non-coated hemofilter achieved overrange at 40？min. This study suggests that BPCA-coated hemofilters can inhibit antithrombin consumption, contributing to antithrombotic effects in extracorporeal circulation circuits