Timing of renal replacement therapy in critically ill patients with acute kidney injury

The only available treatment option of severe acute kidney injury in critically ill patients is renal replacement therapy (1,2). However, a number of issues affecting the optimal use of this primarily supportive technique still remain unresolved (3). The most important question now increasingly being asked is at what point and at which stage to initiate renal replacement therapy in critically ill patients with evolving acute kidney injury. Up to now, the KDIGO guidelines recommend to initiate renal replacement therapy emergently in case of the development of life-threatening complications such as hyperkalemia or severe fluid overload or greater imbalances or disruptions in homeostasis (2).