Blood Compatibility of Circulatory Assist Devices

摘要

The objective was the development of a test for predicting material chemistry effects on blood-material interactions (BMI) under conditions where surface and blood chemistry, and flow were well defined. Acute tests with poly(methylmethacrylate), Cardiothane R and low density polyethylene (LDPE) exposed to native canine blood showed that each material adsorbed a platelet monolayer and polymorphonuclear leukocytes with no appreciable differences in the flow shear required to overcome leukocyte adhesion. Platelet-leukocyte aggregation was inhibited for tests performed with neutral pH and elevated prostacyclin metabolite levels. Hypercapnic acidosis enhanced platelet-leukocyte aggregation. Canine carotid artery 4mm I.D. tube implants (LDPE, polydimethylsiloxane, polyurethane, and polytetrafluoroethylene) ranging from 2 hours to 21 days exhibited an adherent platelet monolayer and varying amounts of noncellular protein deposits. Localized surface defects on each material were thrombogenic. Only the material under evaluation contacted blood. BMI and tube patency appear to be essentially independent of material surface chemistry.