Blood Compatibility of Synthetic Polymers: Perspective and Problems

Abstract

This brief narrative presents the understanding which I believe has been achieved among workers in the field of blood compatibility of nonphysiologic materials. The key problem area remaining to be clarified is that of protein adsorption and its influence on subsequent cell adhesive events. Figure 1 charts the general interactions which occur when blood contacts foreign solid surfaces. It had been thought until the late 1960s that protein adsorption on the solid surface, ultimately leading to blood gelation by pathways involving the numbered coagulation factors (XII, XIII, etc.) was independent of the parallel events of platelet adhesion to the same solid. Initial platelet adhesion to the bare foreign surface, followed by platelet aggregation into the blood stream, was presumed to mimic the kinetic and thermodynamic events observed in platelet aggregation studies in the absence of foreign solid surface contact, ultimately leading to the formation of a white thrombus mass.