Filter Adsorption of Anidulafungin to a Polysulfone-Based Hemofilter During CVVHD In Vitro

Candidemia is frequent in critically ill patients, especially in combination with an acute kidney injury (AKI). Echinocandins generally are recommended for therapy of such infections. Recent studies found no need for dosage adjustment in patients with end-stage renal disease receiving hemodialysis, or patients with AKI receiving continuous venovenous hemofiltration. The aim of this in vitro study was to examine the adsorption of anidulafungin to the surface of the hemofilter during continuous venovenous hemodialysis (CVVHD) and its effect on anidulafungin concentrations. The concentration of anidulafungin in the dialyzed fluid, and the dialysate during CVVHD in vitro was examined using three different dialyzed fluids (saline; saline with 40 g/L human albumin; and a mixture of human erythrocytes and fresh frozen plasma). After the end of dialysis, the hemofilter was opened and portions of the filter capillaries were also analyzed to determine the amount of anidulafungin adsorbed. When dialyzing saline, about 99% of the anidulafungin used adsorbed to the hemofilter capillaries; in the experiments with saline with 40 g/L albumin, about 60% adsorbed to the hemofilter's surface, and when blood was dialyzed, 35% was found adsorbed after analyzing the filter capillaries. Anidulafungin was not detectable in the dialysate of any of the experiments, consequently the dialysis clearance was 0 mL/min. In conclusion, during CVVHD in vitro we found remarkable adsorption of anidulafungin to the hemofilter's surface, yet the effect on the tissue concentration needs further examination.