Renal replacement therapy for acute kidney injury: let's follow the evidence

Abstract

Selection of a dialysis modality for critically ill patients with acute kidney injury (AKI) continues to be a controversial topic. Available studies can be divided into: 1) randomized controlled trials assessing the effect of treatment dose on patient outcome; 2) randomized controlled outcome comparisons of CRRT and IRRT; and 3) observational outcome comparisons of CRRT and IRRT. Clinical outcome comparisons of CRRT and HD continue to be very problematic. With the availability of the recent CRRT dose/outcome data, the interpretation of CRRT vs HD trial data now becomes nearly impossible because of the low-dose ""handicap"" that has existed in all of the comparative trials in the CRRT arms. Randomized and observational outcome studies suffer from several methodological problems and a final statement cannot be made. In the end, CRRT and HD are vastly different therapies that are not mutually exclusive but rather are complementary - they provide different options for patients at variable stages of their AKI course. Very preliminary data from SLED studies suggest this therapy also can be part of the continuum of AKI dialytic modalities. However, the lack of any meaningful outcome data for this therapy invalidates any claims of clinical "equivalence" to the other established modalities.