Background: To date, there are no known methods for preventing acute kidney injury after cardiac surgery. Increasing evidence suggests that erythropoietin has renal antiapoptotic and tissue protective effects. However, recent human studies have shown conflicting results. The authors aimed to study the effect of a single high-dose erythropoietin preoperatively on renal function after coronary artery bypass grafting in patients with preoperative impaired renal function.
Methods: This single-center, randomized, double-blind, placebo-controlled study included 75 patients scheduled for coronary artery bypass grafting with preexisting renal impairment estimated glomerular filtration rate based on p-cystatin C (<60 and >15 ml/min). The patients either received a single high-dose erythropoietin (400 IU/kg) or placebo preoperatively. The primary endpoint was renal protection evaluated by p-cystatin C at the third postoperative day compared to the preoperative values. Incidence of acute kidney injury and other renal biomarker changes were among secondary endpoints.
Results: There was no statistically significant difference on the third postoperative day for relative p-cystatin C level changes from baseline between the groups, 131 ± 31% (mean ± SD) for the study group and 125 ± 24% for the control group (P = 0.31; 95% CI, −0.6 to 20% for the difference). There were no statistically significant differences in other renal biomarkers or measures between the groups (p-neutrophil gelatinase–associated lipocalin, p-creatinine, p-urea, and estimated glomerular filtration rate). There were no other differences in outcome variables between the groups.
Conclusion: Intravenous administration of a single high-dose (400 IU/kg) erythropoietin did not have a renal protective effect on patients with reduced kidney function undergoing coronary artery bypass surgery.