Timing of renal replacement therapy: is it when or how much?

initiation of renal replacement therapy (RRT) in decreasing mortality and ICU length of stay in patients with Acute Kidney Injury Network stage 3 [1]; however, we have a few concerns regarding the study. e impact of fl uid balance on morbidity and mortality in patients with septic shock, especially with acute kidney injury, cannot be understated [2]. is impact can aff ect ventilator-free days and the length of ICU stay. e authors did not show their fi rst 6-hour and 24-hour fl uid balances. Whether the reported improvement was due to the timing of initiation of RRT, the dose, or misrepresentation of the study population is an unanswered question. Were improvements seen in morbidity and mortality simply because more volume was removed because of early initiation of RRT or because patients with more severe disease were not represented in the study? e overall in-hospital mortality in this study was 72%, which is extremely high. In previous prospective studies, the overall mortality rate was just 46% [3]. Were there other variables in management that were not addressed, such as the time from admission to antibiotic treatment, adequate fl uid resuscitation, or initiation vasopressor treatment, which may have led to the high mortality in this population [4]?