Timing of renal replacement therapy in acute kidney injury—an issue of importance?

Acute kidney injury is a common complication in critically ill patients associated with an increased morbidity and mortality (1). It manifests itself in approximately 50% of critically ill patients, and it is, in cases of higher degrees of severity or combinations with other organ failures, associated with mortality rates exceeding 40% (2). Up to now therapeutic options are restricted to the use of symptomatic renal replacement therapy in patients with life-threatening fluid accumulation or greater imbalances or disruptions in homeostasis (3). However, even the optimal management of renal replacement therapy remains elusive (3,4).