Early or late renal replacement therapy for severe acute kidney injury? The Artificial Kidney Initiation in Kidney Injury Trial finds similar outcomes

For patients with stage 3 acute kidney injury (AKI), early and delayed strategies for renal replacement therapy (RRT) yield similar mortality rates, concludes a randomized trial in The New England Journal of Medicine.

The Artificial Kidney Initiation in Kidney Injury (AKIKI) Trial included 620 patients with severe AKI enrolled at 31 French intensive care units (ICUs). All patients had Kidney Disease Improving Global Outcomes (KDIGO) stage 3 AKI requiring mechanical ventilation and/or catecholamine infusion, with no potentially life-threatening complications directly related to kidney failure.

In open label fashion, patients were assigned to early (immediate) or delayed RRT. In the delayed group, RRT was started if the patient developed severe hyperkalemia, metabolic acidosis, pulmonary edema, BUN level greater than 112 mg/dL, or oliguria lasting longer than 72 hours.

The primary outcome of 60-day overall survival was not significantly different between groups. Mortality was 48.5 percent in patients assigned to the early strategy and 49.7 percent in those with the delayed strategy. In the delayed group, 49 percent of patients received no RRT.

Catheter-related bloodstream infections developed in 10 percent of patients with the early strategy versus 5 percent with the delayed strategy (3). Most other complications were similar between groups. Time to adequate diuresis was shorter with the delayed strategy.

There is ongoing debate over the optimal timing of RRT for severe AKI. The AKIKI Trial shows similar mortality in patients with stage 3 AKI assigned to an early versus delayed strategy. The authors point out that their delayed strategy avoids the need for any RRT in about one-half of patients [Gaudry S, et al. Initiation strategies for renal-replacement therapy in the intensive care unit. N Engl J Med 2016, DOI: 10.1056/NEJMoa1603017].