Measured levels of hemostatic factors. The levels are as follows: 1 indicates baseline; 2, after sternotomy; 3, after heparinization; 4, after 5 minutes of cardiopulmonary bypass (CPB); 5, after 15 minutes of CPB; 6, after 30 minutes of CPB; 7, 5 minutes prior to reperfusion of heart and lungs; 8, 5 minutes after reperfusion; 9, after protamine infusion; and 10, 2 hours after surgery. Center point indicates mean; box, standard error of the mean; and error bars, standard deviation; n = 9. The solid black box in each graph indicates the period of CPB.