Continuous renal replacement therapy: mechanism of clearance, fluid removal, indications and outcomes

Purpose of review Continuous renal replacement therapy (CRRT) is the most common dialysis modality provided to critically ill children with acute kidney injury (AKI). However, confusion still exists with respect to CRRT terminology and the optimal use of this modality across the entire pediatric disease and age spectrum. Recent findings Data from both single-center and multicenter pediatric studies demonstrate that CRRT can be provided effectively to all pediatric patients, from infants to young adult aged patients. Furthermore, these data demonstrate a consistent and independent association between the degree of patient fluid accumulation at the initiation of a CRRT course and mortality in critically ill children with AKI. In addition, CRRT has been successfully utilized for rapid clearance of both exogenous and endogenous (e.g., ammonia) toxins without the concentration rebound that characterizes toxin removal by intermittent hemodialysis. Summary CRRT represents an essential dialytic modality for the pediatric nephrologist caring for critically ill children. Current data suggest that earlier initiation of CRRT to prevent excessive fluid accumulation may lead to improved survival in critically ill children, but prospective trials are required to test this hypothesis directly.