Continuous arteriovenous hemofiltration in experimental iron intoxication

This study evaluated continuous arteriovenous hemofiltration (CAVH) as a method for removing the iron-deferoxamine complex in experimental iron intoxication. Five anesthetized dogs were instrumented for hemodynamic monitoring and then given 600 mg/kg of elemental iron as ferrous sulfate. After a 3-h absorption period, CAVH was begun from the femoral artery to femoral vein. Deferoxamine was infused into the arterial lines of the CAVH cartridge at increasing doses. We found a dose-dependent increase in the ultrafiltrate excretion of iron. However, most of the deferoxamine was excreted unbound. The efficiency of complex formation was greater at lower BP and ultrafiltrate formation rate, suggesting that inadequate mixing of deferoxamine with blood may occur when arterial administration is used. Iron excretion in the urine over the same time period was not significantly greater than that removed by CAVH. We conclude that CAVH can remove iron using deferoxamine as a chelating agent.