Pharmacological strategies for blood conservation in cardiac surgery: erythropoietin and antifibrinolytics.

ABSTRACT

PURPOSE: We review the clinically important benefits of the two principal pharmacological strategies, erythropoietin (EPO) and antifibrinolytics (aprotinin and lysine analogues), to decrease transfusion of allogeneic blood products (ABP) during and after cardiac surgery. SOURCE Articles were selected from an ongoing review of the literature, with special attention to meta-analyses dealing with EPO and/or antifibrinolytics and cardiac surgery. PRINCIPAL FINDINGS: The few studies available include a number of patients insufficient to allow definitive conclusions on the benefits of EPO in cardiac surgery. Further studies are required to determine the optimal dose of EPO and to compare its cost-effectiveness with other blood sparing strategies in this context. Both aprotinin and lysine analogues effectively decrease ABP transfusions and the incidence of re-thoracotomy. In addition, high-dose aprotinin reduces cerebrovascular morbidity and mortality after cardiopulmonary bypass. Several mechanisms have been put forward to explain these beneficial effects, some of which could well be common to all antifibrinolytics. The clinical benefits of aprotinin's unique anti-inflammatory effect are not entirely clear but the finding that it reduces the incidence of stroke and death is certainly a major argument in favor of its utilization. Yet, we have to ensure that aprotinin's benefits are not offset by side-effects such as allergy. CONCLUSIONS: We still need large scale studies to definitely confirm the benefits and exclude the deleterious effects of these drugs on outcomes other than ABP requirements. At present, aprotinin is the only agent that has been shown to reduce the risk of cerebrovascular accident and mortality after cardiac surgery in adults.