BIOCOMPATIBILITY OF EXTRACORPOREAL CIRCULATION : IN VITRO COMPARISON OF HEPARIN-COATED AND UNCOATED OXYGENATOR CIRCUITS

Oxygenator/tubing sets coated with endpoint-attached heparin were compared to uncoated sets in a dynamic model of extracorporeal circulation. Biocompatibility was assessed by evaluations of complement activation and platelet loss. The median concentration of C3 activation products increased gradually from 12 AU/ml at baseline to 65 AU/ml after 120 minutes in the uncoated sets and from 12 AU/ml to 19 AU/ml after 120 minutes in the coated sets (p<0.002). The median concentration of the terminal complement complex in the uncoated sets increased gradually from 3.1 AU/ml at baseline to 18.2 AU/ml after 120 minutes. In the coated sets the terminal complement complex reached a peak of 12.0 AU/ml at 15 minutes and returned to baseline values at 60 minutes. Median platelet loss at 120 minutes was 166×10 9 in the uncoated and 21×10 9 in the coated sets (p<0.01). Heparin coating thus improved biocompatibility by reducing both complement activation and platelet loss