Identifying critically ill patients with acute kidney injury for whom renal replacement therapy is inappropriate: an exercise in futility?

Clinicians treating critically ill patients must consider the possibility that painful and expensive aggressive treatments might confer negligible benefit. Such treatments are often described as futile or inappropriate. We discuss the problem of deciding whether to initiate renal replacement therapy (RRT) for critically ill patients with acute kidney injury (AKI) in the context of the debate surrounding medical futility. The main problems in deciding when such treatment would be futile are that the concept itself is controversial and eludes quantitative definition, that available outcome data do not allow confident identification of patients who will not benefit from treatment and that the decision on RRT in a critically ill patient with AKI is qualitatively different from decisions on other modalities of intensive care and resuscitation, as well as from decisions on dialysis for chronic kidney disease. Despite these difficulties, nephrologists need to identify circumstances in which continued aggressive care would be futile before proceeding to initiate RRT.