Delay renal replacement in severe sepsis with acute kidney injury: IDEAL-ICU

Another large study suggests that there is no benefit to early initiation of renal replacement therapy (RRT) in patients with severe sepsis with septic shock and acute kidney injury (AKI). And many patients whose renal replacement was delayed recovered sufficient kidney function to avoid dialysis entirely.

Because AKI is associated with worse outcomes in critical illness, and restoration of more-normal lab values is widely assumed (incorrectly) to always be a good thing in itself, early renal replacement is the standard in many ICUs. Early studies were equivocal on the subject, suggesting possible benefits , no benefit, or harms associated with early RRT.

Then the 2017 AKIKI randomized trial showed no benefit from early RRT in AKI due to severe critical illness, among 620 patients at French centers. Almost half the patients in the delayed RRT group avoided dialysis altogether.

Only 30% received continuous renal replacement therapy (CRRT) -- the French appear more inclined to use conventional hemodialysis in patients on vasopressors, compared to the tendency toward use of CRRT in patients with shock in U.S. ICUs.

IDEAL-ICU: Delaying RRT in AKI from Sepsis May Be Beneficial

The work of a separate group of French investigators bolsters the argument that early RRT does not help patients with septic shock and AKI, as compared to delaying RRT. The findings of their IDEAL-ICU trial were published in the New England Journal of Medicine.

Patients with septic shock and severe acute kidney injury (creatinine 3x baseline or oliguria/anuria) were randomized to either undergo RRT within 12 hours, or after at least 48 hours. All patients were on vasopressors and ~90% were mechanically ventilated. Those requiring immediate RRT (for severe hyperkalemia, severe acidosis, etc.) were excluded.

At 90 days, 54% of those in the delayed-RRT group had died, compared to 58% of those in the early-RRT group.

Authors had intended to randomize 864 patients, but after analysis of the first 488, the trial was stopped early for futility.

More than a third of those in the delayed-RRT group recovered renal function and avoided dialysis/CRRT. About one in six patients in the delayed-RRT group required emergency RRT, usually for hyperkalemia.

Like the AKIKI trial, directly extrapolating the findings of IDEAL-ICU from France to the U.S. may be premature. French physicians had the option of using peritoneal dialysis or hemodialysis on study patients, instead of CRRT. In many U.S. centers, CRRT is standard for patients in shock on vasopressors.

That said, given the robustness of IDEAL-ICU's findings, along with AKIKI, it seems highly unlikely that early CRRT would improve outcomes over delayed RRT, either. In the absence of anuria or other indications for urgent renal replacement therapy, closely observing for at least 48 hours to await return of kidney function seems most appropriate for most critically ill patients with AKI.

Source: NEJM