Dialysis strategies in critically ill acute renal failure patients

Acute renal failure requiring dialysis is a frequent complication in critically ill patients, with a high morbidity and mortality. Until now, no evidence-based guidelines on the optimal treatment of acute renal failure on the ICU are available. This article reviews recent publications that shed light on several specific topics, like optimal treatment modality, dose of dialysis, type of dialysis membrane, and new developments such as slow extended daily dialysis.

For a long time, it has been claimed that continuous renal replacement therapies were superior to intermittent hemodialysis. Several recent articles addressed this topic, but none of them could demonstrate superiority of one of the two modalities. A meta-analysis confirmed this lack of differences in outcome. A landmark study underscored the importance of dose of dialysis in continuous renal replacement therapy. Although a comparable study in intermittent hemodialysis is still lacking, it was shown that daily dialysis is an absolute prerequisite for adequate intermittent hemodialysis. A meta-analysis further demonstrated that the use of biocompatible membranes can influence patient survival positively, without effect on recovery of renal function. Slow extended daily dialysis emerged as a hybrid renal replacement therapeutic modality and has promising features because it combines the advantages of both continuous renal replacement therapy and intermittent hemodialysis.

Adequate dialysis is needed to reduce mortality related to acute renal failure in ICU patients. This necessitates an approach that is completely different from that in chronic renal failure.