No Added Mortality Benefit from Current Approaches to Renal Replacement Therapy in Icu Patients

Hospital-acquired acute kidney injury (AKI), a common and harmful renal disorder, is an independent risk factor for short-term and long-term mortality particularly in critically ill patients. The management of this patient subpopulation remains supportive, with renal replacement therapy (RRT) indicated in severe renal failure. RRT prevents immediate death from lethal complications of advanced AKI, and undoubtedly reduces the mortality in AKI patients. The field of RRT has undergone remarkable changes to further improve the dismal short-term outcome. However, trials have failed to demonstrate an additional survival benefit of choice of modality or increased dose, or timing of RRT initiation if RRT is adequately performed. Clearly, AKI is not an isolated event but results in multiple negative effects on inflammation or coagulation and in multiple organ dysfunction. The underlying mechanisms are not amenable to current RRT. Thus, we should be realistic in our expectations of what dialysis and haemofiltration could accomplish; they are not renal replacement therapies in the true sense of the word, but only supportive systems. Prevention of AKI by better care, earlier anticipation of AKI by use of novel biomarkers and pharmacologic therapy of emergent AKI, and the introduction of bioreactor systems into clinical treatment of AKI may be future strategies to further improve the poor outcome of these patients.