Impaired hemostasis of multiple etiologies are often present in patients undergoing cardiopulmonary bypass surgery. Microvascular bleeding caused by dysfunctional platelets and impaired coagulation cascade occur during CPB secondary to foreign surface contact. The detection of coagulation abnormalities including platelet dysfunction reduces the risk of both intra and postoperative blood loss. Although ACT remains the most widely used clinical test the reason of inadequacy of ACT - based heparinization is that ACT monitorization is based on contact activation which may not be the represantative of CPB. Because heparinization requires monitoring and although antifactor X a activity measurements are considered the gold standart tromboelastography and other point of care devices are reviewed here to achieve major advances in blood conservation methods.