Background: The risks of homologous blood product transfusions have led to emphasis on blood conservation and use of autologous products. Intraoperative collection of platelet-rich plasma (PRP) allows autotransfusion of fresh platelets and clotting factors at the completion of cardiopulmonary bypass (CPB). Methods: In a retrospective review, the results of 14 patients who underwent replacement of the ascending aorta and aortic valve with a composite graft with intraoperative plateletpheresis before CPB were compared with a control group of 17 patients. Results: There were no differences in age, weight, length of CPB, duration of aortic cross-clamping or other major risk factors between the groups. In the treatment group, 406 ± 99 (s.d.) mL of PRP was collected. This contained 2.54 ± 1.35 x 1011 platelets, or 23 ± 6% of estimated preoperative circulating platelets. Cumulative mediastinal chest tube drainage was reduced in the PRP group at 8 hours (459 ± 162 vs 799 ± 580 mL, p = 0.03), and 24 hours (695 ± 272 vs 1267 ± 891 mL, p = 0.03). Homologous blood products transfused were 5.4 ± 8.3 units in the PRP group vs 17.7 ± 21 in the controls (p = 0.01). Conclusion: Our retrospective review suggests that intraoperative plateletpheresis may be useful in reducing postoperative blood loss and homologous transfusions in patients undergoing composite graft replacement of the ascending aorta and aortic valve. A prospective study is warranted.