More aggressive kidney dialysis for patients with acute kidney injury does not reduce death, improve kidney function, or reduce the rate of organ failure.

Acute kidney injury is a well known complication of critically illness, occurring in roughly one-third of patients in the ICU. Approximately 6% of critically ill patients will suffer from acute kidney injury severe enough to require dialysis and for these patients hospital mortality is approximately 50-80%.

Previously, single-center studies have suggested that more intensive dialysis improved outcomes. However, the Acute renal failure Trials Network (ATN) study, lead by Dr. Paul Palevsky (professor of medicine at Pitt) found that more dialysis was not better. The study results were released early, in the May 20 online edition of the New England Journal of Medicine (http://content.nejm.org/cgi/content/full/NEJMoa0802639), to coincide with a presentation at the American Thoracic Society's International Conference, in Toronto.

Dr. Ramesh Venkataraman (Pitt CCM alumnus and former faculty member) was also a co-investigator. Drs. Kellum and Venkataraman and the rest of the ATN investigators randomly assigned 1,124 patients with acute kidney injury to receive intensive or less intensive dialysis. Patients who received intensive renal therapy had dialysis six times a week, while patients who received less intensive renal therapy, underwent dialysis three times a week. Hemodynamically unstable patients received continuous renal replacement therapy at either 20ml/kg/hr or 35 ml/kg/hr depending on which group they were randomized to.

The study found that the rate of death, after two months, was 53.6 percent among patients receiving intensive renal therapy and 51.5 percent among patients receiving less intensive therapy. Moreover, there was no difference between the groups in the length of time renal replacement therapy was given, the recovery of kidney function or failure of other organs, the researchers found.

However, the lower intensity that we studied was significantly greater than that currently being given to many patients. A previous study conducted in Germany which found an improvement in outcome with more dialysis compared this to an intensity of dialysis much lower than currently recommended or used in the ATN trial. Thus, clinicians need to be vigilant to ensure that sufficient dialysis is provided to critically ill patients. This is especially important because many of sickest patients require a concerted effort among multiple clinicians to ensure that they receive the recommended intensity of dialysis. Many patients don’t currently get this because it takes a lot of time and skill to provide it.  

ATN Study Logos: Intensive vs Conventional Renal Support in Acute Renal Failure (PDF)