When to start renal replacement therapy in critically ill patients with acute kidney injury: comment on AKIKI and ELAIN.

The dilemma of whether and when to start renal replacement therapy among critically ill patients with acute kidney injury in the absence of conventional indications has long been a vexing challenge for clinicians. The lack of high-quality evidence has undoubtedly contributed decisional uncertainty and unnecessary practice variation. Recently, two randomized trials (ELAIN and AKIKI) reported specifically on the issue of the timing of initiation of renal replacement therapy in critically ill patients with acute kidney injury. In this commentary, their fundamental differences in trial design, sample size, and widely discrepant findings are considered in context. While both trials are important contributions towards informing practice on this issue, additional evidence from large multicenter randomized trials is needed.