Intensity of renal replacement therapy in acute kidney injury: perspective from within the Acute Renal Failure Trial Network Study

Abstract

Determination of the optimal dose of renal replacement therapy in critically ill patients with acute kidney injury has been controversial. Questions have recently been raised regarding the design and execution of the US Department of Veterans Affairs/National Institutes of Health Acute Renal Failure Trial Network (ATN) Study, which demonstrated no improvement in 60-day all-cause mortality with more intensive management of renal replacement therapy. In the present article we present our rationale for these aspects of the design and conduct of the study, including our use of both intermittent and continuous modalities of renal support, our approach to initiation of study therapy and the volume management during study therapy. In addition, the article presents data on hypotension during therapy and recovery of kidney function in the perspective of other studies of renal support in acute kidney injury. Finally, we address the implications of the ATN Study results for clinical practice from the perspective of the study investigators.

Figure 1

All-cause mortality at 60 days as a function of days managed using intermittent hemodialysis. The time in the intermittent hemodialysis (IHD) phase was defined as the number of days from the first IHD treatment or from the first day after continuous renal replacement therapy (CRRT) or sustained low-efficiency dialysis (SLED) was discontinued until the last day of IHD treatment, the last day before initiation of CRRT or SLED, or the discontinuation of study therapy. Days with IHD and with either CRRT or SLED were counted as in the IHD phase. The percentage of days managed using IHD was calculated by dividing the number of days in the IHD phase by the total number of days of study therapy.