Controversies in acute kidney injury: effects of fluid overload on outcome.

Fluid management in critically ill patients is a complex process as aggressive fluid resuscitation is commonly utilized for initial hemodynamic support and fluid administration often contributes to fluid retention, particularly when there is impaired kidney function. Recent evidence suggests that fluid accumulation is associated with adverse outcomes. It is unclear whether fluid retention is simply a marker of the severity of organ failure or a mediator of events. In this article we review the evidence and provide a framework for future studies to refine these concepts further.