Aspirin Decreases Platelet Uptake on Dacron Vascular Grafts in Baboons

Abstract
The influence of a single dose of aspirin (5.4-7.4 mg/kg) on platelet uptake on 4-mm Dacron interposition grafts was studied in a baboon model using .gamma. camera scanning for 111In labeled platelets. In vitro assessment of platelet function after aspirin administration revealed that in the baboon, as in the human, aspirin abolished arachidonic acid-induced platelet aggregation, prolonged the lag time between exposure to collagen and aggregation, and decreased plasma thromboxane B2 levels. Asprin also prolonged the template bleeding time. Scans for 111In labeled platelets revealed that pretreatment with a single dose of aspirin decreased platelet uptake on 4-mm Dacron carotid interposition grafts. This decrease in platelet uptake was associated with a significant improvement in 2-h graft patency and with a trend toward improved 2-wk patency.