Thrombogenic vascular graft and blood collection device. Thrombogenesis started and thrombi developed in a collagen-coated (4-mm internal diameter [id]) expanded-polytetrafluoroethylene vascular graft that was deployed for 60 minutes into a chronic high flow arteriovenous shunt in healthy baboons. Blood samples were drawn from the coagulation marker concentration boundary layer by a syringe pump 1 cm downstream from acutely developing thrombi. PPACK anticoagulant was infused 3 mm proximal to the sample port to prevent the sample port from occluding during the 1-hour study. Blood flow through the graft was maintained at a fixed rate of 100 mL/min for the entirety of each study by proximal clamping.