EPO and acute kidney injury: Secondary end-points included the distribution of patients in each KDIGO level within the first 48 h among the two groups, the occurrence of AKI through day-28 or ICU discharge, the presence of AKI at the 48th hour using only the creatinine criteria of the KDIGO classification, the hematopoietic effects of Epo through day-28 or ICU discharge, the day-28 glomerular filtration rate estimated with the MDRD equation, and side effects.