To the Editor The Early vs Late Initiation of Renal Replacement Therapy on Mortality in Critically Ill Patients With Acute Kidney Injury (ELAIN) trial reported decreased mortality with early vs delayed renal replacement therapy (RRT) initiation in critically ill patients with acute kidney injury (AKI).1 In contrast, the Artificial Kidney Initiation in Kidney Injury (AKIKI) trial found no mortality difference with early vs delayed strategies.2 However, the design of the 2 studies was different. In the AKIKI trial, late initiation was based on typical absolute criteria (hyperkalemia, metabolic acidosis, pulmonary edema, severe oliguria) compared with a time-frame initiation (<12 hours of reaching Kidney Disease: Improving Global Outcomes [KDIGO] stage 3 AKI) in the ELAIN trial. The case-mix in the 2 studies was different. In the ELAIN study, the population was mostly postoperative patients with approximately 50% having had cardiac surgery, whereas in the AKIKI study, the population was mainly medical (around 80% had sepsis).
Vinsonneau C, Monchi M. Timing of Initiation of Renal Replacement Therapy in Critically Ill Patients With Acute Kidney Injury. JAMA. 2016;316(14):1497-1498. doi:10.1001/jama.2016.11329