Background: Acute kidney injury (AKI) is a common postoperative complication after heart surgery with cardiopulmonary bypass (CPB). Multiple studies have demonstrated that patients with AKI have worse clinical outcomes, such as longer ventilation times and increased length of stay, which is thought to be secondary to associated oliguria and subsequent fluid overload. Studies suggest that early renal replacement therapy (RRT) via peritoneal dialysis (PD) may prevent fluid overload and therefore be a superior management to diuretic (i.e. furosemide) administration. However, there is no published evidence to suggest superiority or laboratory data available to guide decision making.