Antifibrinolytic Therapy for Cardiac Surgery An Update

"Antifibrinolytic agents" reduce fibrinolysis in cardiac surgery, blood loss, chest tube drainage, and transfusion requirements. Although, the mechanisms of action are complex, and involve various biochemical pathways, they are not completely elucidated and have clinically relevant side effects. Recent studies and drug development evaluating other novel serine protease inhibitors were terminated prematurely due to an increased incidence of adverse events. Although aprotinin will be reintroduced in certain countries, its use will be restricted to limited indications. Before these indications can be extended again to complex surgical procedures, additional safety studies will be needed. Despite the extensive use of EACA in the United States, clinical safety and efficacy data are limited, and there are increased risks for postoperative renal dysfunction after EACA administration. On the basis of the reports for aprotinin and TXA, which have been extensively used for many years before significant side effects were associated with their use, we believe that the safety and efficacy profile of EACA needs further investigation. The relation between TXA dosing and clinical seizures and their impact on clinical outcomes need further investigations. Open-heart procedures may play a role in this regard as the incidence of seizures and an increased mortality had been associated with TXA in this patient population. The large CRASH-2 trial of TXA in trauma patients showed that a low-dose TXA protocol (approximately 2 g in adults) in high-risk patients translated into a reduction of mortality. Because of dose-dependent side effects of TXA, we believe that a low-dose TXA protocol should be preferentially used in cardiac surgery.