Outcomes of pediatric solid tumors have improved dramatically over the years and their management often requires a multidisciplinary team approach. Many of these tumors require chemotherapy as well as surgical resection. Surgical complications can contribute to mortality and morbidity. Acute kidney injury (AKI) is an important perioperative complication. Prevention, early detection, and prompt management of AKI are crucial elements to limit morbidity. Initial management of AKI in the postoperative stage may include fluid resuscitation if hypovolemia is suspected. When fluid overload (FO) is present, restriction of fluid intake as well as diuretics administration are undertaken as measures to ameliorate FO. Renal replacement therapy (RRT) is efficient in reversing metabolic derangements and fluid overload when indicated in the postoperative phase. RRT can be delivered intermittently or continuously depending on patient’s fluid status and hemodynamic status. This chapter provides an overview of the different modalities of RRT, indications, challenges, and potential complications encountered with this therapy.