The assessment of fractional drug removal by extracorporeal dialysis.

It is generally concurred that the effectiveness of extracorporeal dialysis is best evaluated by fractional drug removal, i.e. the proportion of body burden of drug removed during the period of dialysis treatment. Two equations reported in the literature and five equations proposed in this article are examined for their validity in the assessment of fractional drug removal. Potential limitations and applicable conditions of these equations are discussed and compared. Calculations of fractional drug removal are demonstrated using both simulated and experimental data of ethambutol. Depending on the available kinetic measurements during dialysis and post dialysis, one may apply each equation separately or in conjunction with others to the calculation of fractional drug removal.