Recent studies have shown an increased incidence of renal replacement therapy after the use of Hydroxyethylstarchs (HES) in patients admitted in the intensive care unit. However, studies showing detrimental effects of HES have been conducted in mostly non-surgical subjects. There are very few studies analyzing the effects of HES on renal function after cardiac surgery, a population already at risk of renal dysfunction.

Inclusion Criteria:

• All patients undergoing cardiac surgery

Exclusion Criteria:

• Heart transplantation
• Ventricular assist devices
• Patients requiring extracorporeal life support before or after cardiac surgery
• Patients revised for bleeding and/or tamponnade presenting with hemodynamic instability
• Patients in whom the administered volume therapy was not completely available
• Subjects who required renal replacement therapy before surgery
• Trauma patients who were put on cardiopulmonary bypass
• Patients who died intra-operatively or soon after arrival in the intensive care unit in whom no postoperative creatinine measurements were available