Inclusion Criteria:  Age 18 to 65 years old. Patient planned with elective cardiac surgery such as CABG, one cardiac valve replacement, one cardiac valve repair or two valves, CABG and replacement/repair one cardiac valve. Cardiac surgery performed using cardiopulmonary bypass machine. Patient with mild to moderate kidney dysfunction (GFR 30-89 mL/min/1.73m2) and never got renal replacement therapy before.  Exclusion Criteria:  Cardiac ejection fraction <40%. Patient with new preoperative acute renal failure by any cause. Sudden shift in cardiac surgery timing (emergency cardiac surgery or repeated procedure). Complex cardiac disease associated with intra aortic balloon pump use, replacement of more than two cardiac valves, coronary artery disease with severe valve disease, and patient with pulmonary hypertension, and cardiac surgery procedures for congenital heart disease. Patient with aortic abnormality, and/or has direct effect on renal artery. Patients concurrently enrolled in other study with other drugs being studied. Patient with hemodynamic disturbance caused by hemorrhage, sepsis, anaphylactic, or cardiogenic shock. Patient refuses to participate in the study.