Abstract
Three methods of continuous renal replacement therapy, continuous hemodialysis (CHD), continuous hemofiltration (CHF) and continuous hemodiafiltration (CHDF) were compared using a polyacrylonitrile filter. Clearance of blood urea nitrogen, vitamin B12, dextran, cytochrome C, and myoglobin was calculated at various dialysate and/or filtration flow rates. With CHF, clearances of all substances measured increased linearly as the filter flow rate increased. With CHD, a linear increase of clearance was observed only for blood urea nitrogen. Increased clearance due to increases in dialysate flow rate was less for substances with greater molecular weights. The results of CHDF were always between those of CHF and CHD. For substances with higher molecular weights, clearance was highest with CHF.
