Findings from two large randomized controlled trials on renal replacement therapy in acute kidney injury

Many issues regarding the management of renal replacement therapy (RRT) in acute kidney injury (AKI) including timing of initiation, selection of RRT modality, and optimal dosing remain to be resolved. Two major randomized controlled trials, the Veterans Affairs/National Institutes of Health (VA/NIH) Acute Renal Failure Trial Network (ATN) and the Randomized Evaluation of Normal versus Augmented Level (RENAL) studies, which were elaborately designed to evaluate the benefit for delivering RRT of higher intensity in critically ill patients, were characterized by their sophisticated design, large sample sizes, and comprehensive data collection. Although no beneficial effect of higher intensity RRT was demonstrated by these studies, many ancillary studies conducted subanalyses which provided additional findings on other important clinical questions that remained unsolved. This review aims to overview the useful information obtained by the VA/NIH ATN and the RENAL studies to gain useful insights for optimal RRT in AKI.