Recently, technological developments in hemodialysis techniques and the continuous renal replacement therapies have limited the indications for peritoneal dialysis (PD) in critically ill patients with acute kidney injury (AKI). However, PD remains an effective therapy that is easily and simply instituted, especially for infants (weighing less than 2500 g) and children with AKI. Highly trained personnel, expensive and complex apparatus, and systemic anticoagulation, vascular access were not needed, and so the procedure could be simply and quickly initiated. Peritoneal access should be implanted surgically by surgeon (laparascopic technique if possible) or the bedside-placed acute catheter. We can use continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD). In practice APD can be performed successfully in infants only when the fill volume is over 100–150 ml. If an infant needs acute dialysis it is important to use low fill volumes (200 ml/m² or 10 ml/kg) and frequent exchanges after catheter implantation to avoid leakage and continuous dialysis with dwell time of 30–50 min. It is possible to achieve sufficient ultrafiltration and purification in anuric infants with a high glucose concentration dialysis solution. Lower fill volumes are used for 5–7 days, after which the amount is gradually increased to 800–1000 ml/m², and the exchanges reduced to 8–12 per 24 h. The acute PD catheter needs careful attention, because catheter-related infections continue to be the most common complication of acute PD and the most frequent cause of catheter removal.