Trillium coating of cardiopulmonary bypass circuits improves biocompatibility

Coating of cardiopulmonary bypass circuits may be a solution to prevent adv erse effects induced by contact of blood elements with foreign surfaces. Us ing an animal model, we investigated the Trillium(TM) coating of cardiopulm onary bypass circuits (a new process involving polyethylene oxide, sulphona te groups and heparin) at low systemic heparinization, focusing on haemolys is and clot formation. Cardiopulmonary bypass was initiated through jugulo-carotid acess with ACT maintained around 180 sec. Treated circuits (Trillium group) were evaluated in 3 calves (mean weight of 66.0+/-8.7 kg), vs. untreated circuits in 3 co ntrol calves (mean weight of 60.7+/-7.5 kg). Blood samples were drawn at re gular intervals for biochemical, hematological and blood gas analyses. Afte r 6 consecutive hours, the animals were weaned from CPB and were awakened. The circuits were analyzed for clot deposits. After 7 days the animals were sacrificed and an autopsy was carried out. Red cell and white cell counts did not change over the 6 hours. Platelet counts dropped to 75.9+/-7.3% of the baseline value in the Trillium group after 6 hours whereas counts dropp ed to 57.2+/-26.0 in the control group (p<0.05). Plasma free Hb remained co nstant in the Trillium group but increased significantly to 280+/-65% of ba seline value in the control group (p<0.05). The amount of clots were signif icantly higher in the control group, in the connectors, the reservoir the h eat exchanger and the oxygenator No renal emboli were seen in the Trillium group whereas the mean number of emboli was 3.0+/-2.4 in the control group. We conclude that Trillium coating significantly improves the biocompatibili ty of artificial surfaces exposed to blood.