1A21 Quantitative evaluation of extrinsic and intrinsic blood coagulation reaction rate due to shear rate

Abstract

In vitro antithrombogenic testing is a useful evaluation method for centrifugal blood pumps. We have been making clear a quantitative thrombosis model due to shear rate at between 0 and 2,880 s^<-1> for 3 hours and ACT between 200 and 1,000 s using a double-cylinder type rheometer, and apply to experimental conditions of the in vitro antithrombogenic testing. We focused on the blood coagulation reaction velocity of the coagulation factors under shear field. Porcine blood was used. After sheared, the plasma was obtained, prothrombin time (PT) and activated partial thromboplastin time (APTT) and the reaction velocity for the blood coagulation factors of II, V, VII, VIII, IX, X, XI and XII were measured using human diagnostic reagents by spectrophometry. As results, APTT was prolonged while PT was shortened. The intrinsic system was promoted while the extrinsic system was inhibited in vitro under shear field at 2,880 s^<-1> up to 3 hours, after measured reaction velocity of blood coagulation factors.