Continuous renal replacement therapies in sepsis: Where is the evidence?

SummarySepsis-related acute renal failure (ARF) is a common occurrence and is associated with a high mortality rate, especially when it complicates an already existing clinical picture of multiple organ dysfunctions. As the same pathophysiologic mechanisms working in the systemic circulation act in the renal microvascular network and are triggered by a host of mediators released by the patient's immunitary cells, it has been hypothesized that continuous renal replacement treatments (CRRT) could be used to treat the ARF and to remove the septic mediators at the same time. Indeed, many even if not all experimental and clinical studies demonstrated the both goals are achievable, even if the net effect on the survival is not clear. Several factors including the selection of patients, their different clinical course (early vs. advanced stage of sepsis), the technique used (haemofiltration vs. hemodiafiltration; low vs. high volumes) and endpoints (survival vs. control of uremia) of the studies account for a persisting lack of definite and unequivocal results. In positive studies, a major role for both the early application and the intensity of CRRT has been enlighted.