The role of continuous renal replacement therapy in the treatment of poisoning

Extracorporeal elimination of drugs and toxins is a critical component in the management of poisonings, though specific techniques and indications remain a matter of debate. Conventional hemodialysis is frequently the treatment of choice because of its widespread availability and proven effectiveness for certain drugs and toxins. With the increased availability of continuous renal replacement therapy (CRRT) modalities, there is yet another therapeutic option, but one that has yet to find a definitive role in this field. The continuous nature of these therapies is attractive for the management of acute renal failure, but the relatively slower clearance rates as compared to conventional hemodialysis is a distinct drawback in patients with acute xenobiotic-induced toxicity. There are abundant case reports as well as a few small case series in the medical literature documenting the use of CRRT, but specific techniques and the clinical outcomes vary considerably. Therefore one cannot draw definitive conclusions regarding benefit. Some patients, particularly those who are hemodynamically unstable and are not candidates for conventional hemodialysis, may warrant a trial of CRRT. However, at the present time, routine use for the treatment of poisoning is not supported. Controlled trials to better clarify its role would be beneficial, though such studies would be extremely difficult to conduct in this field. We believe that the intelligent application of extracorporeal modalities requires a thorough knowledge of drug pharmacokinetics, of the techniques utilized, and a skeptical analysis of the available literature.