RESUMO
OBJECTIVE: Preliminary data showed an increase in endogenous erythropoietin (EPO) concentrations after acute normovolemic hemodilution (ANH) in patients undergoing coronary artery bypass graft (CABG) surgery. Numerous studies have shown the organ protective properties of EPO. The aim of this study was to investigate the cardioprotective effects of these increased EPO concentrations that resulted from ANH during cardiac surgery. DESIGN: A prospective, randomized, blind study. SETTING: A university hospital. PARTICIPANTS: A total of 93 patients undergoing isolated CABG surgery with or without cardiopulmonary bypass (CPB). INTERVENTIONS: Subjects with CPB were randomized into the control (C) or ANH group. Those in the off-pump coronary artery bypass group underwent no treatment. In the ANH group, a precalculated amount of blood was withdrawn and replaced by colloids after the induction of anesthesia. MEASUREMENTS AND MAIN RESULTS: Hemodynamic parameters were recorded intra- and postoperatively. Troponin concentrations were measured as a routine parameter postoperatively. Upon intensive care unit arrival, the EPO levels were higher in the ANH group than in the C group. There was no significant difference between the troponin values of the C and the ANH groups at 4 hours postoperatively. CONCLUSIONS: In patients undergoing CABG surgery on CPB, an increase in endogenous EPO concentrations in the physiologic range has no cardioprotective effects.