Effect of Foreign Surface Pacification with Albumin, Aprotinin, Propofol, and High-density Lipoprotein

Foreign surface pacification may significantly reduce the detrimental effects of the cardiopulmonary bypass (CPB) circuit. To date, albumin is the only intervention consistently shown to be beneficial. The cationic physical properties of aprotinin and the known negative charge on the plastic CPB circuit mean that aprotinin binds to the CPB circuit and membrane oxygenator. A previously validated model involving a parallel plate glass slide technique was used. The effects of albumin, aprotinin, propofol, and high-density lipoprotein (HDL) were assessed by the ability to inhibit platelet adhesion to the glass slide surface. The experiment was repeated with collagen-coated glass slides to reproduce the clinical effect of endothelial denudation. The interventions were repeated on membrane oxygenators that are used for CPB. Aprotinin resulted in a minimal reduction in platelet adhesion to uncoated or collagen-coated glass slides. HDL significantly reduced platelet adhesiveness to uncoated or collagen-coated glass slides. Human albumin solution (HAS) and propofol produced an intermediary inhibitory effect on platelet adhesion on both collagen-coated and uncoated glass slides. The same effect was seen with membrane oxygenators that are used during CPB. HDL produced a significant reduction of neutrophil activation when used to coat a membrane oxygenator. Foreign surface pacification with HDL may have beneficial effects as assessed by platelet adhesiveness in a parallel plate assay. Aprotinin had minimal effect, and propofol had an intermediate effect. The same results were obtained using membrane oxygenators, confirming the validity of the parallel plate technique as clinically valid.