Delaying Renal Replacement Therapy for Critically Ill Patients: How Long Is Too Long?

Many critically ill patients develop acute kidney injury (AKI). Multiple studies have shown no benefit to initiating renal replacement therapy (RRT) early and have demonstrated that substantial numbers of patients will avoid RRT entirely if we don't jump to intervention (e.g., NEJM JW Gen Med Aug 15 2018 and Am J Respir Crit Care Med 2018; 198:58). However, how long is “too long” to delay RRT?

Investigators from France randomized 278 patients with either respiratory failure or shock and persistent AKI (i.e., Kidney Disease Improving Global Outcomes stage 3) to either delayed or more-delayed RRT. Patients in the delayed strategy received RRT if they had oliguria or anuria for longer than 72 hours or elevated blood urea nitrogen (BUN; 112–140 …