Superiority of Hemofiltration to Hernodialysis for Treatment of Chronic Renal Failure: Comparative Studies Between Hernofiltration and Hernodialysis on Dialysis Disequilibrium Syndrome

Comparative studies on dialysis disequilibrium syndrome and vascular instability were performed with patients on conventional hemodialysis and on post‐dilution hemofiltration. Sixteen patients on a chronic hemofiltration program were studied and a cross‐over study protocol examining the dialysis disequilibrium syndrome was carried out contrasting hemodialysis and hemofiltration. All patients showed a comparative intolerance to conventional hemodialysis. A notably lower incidence of dialysis disequilibrium syndrome was observed in hernofiltration than in hemodialysis. The effect of hemofiltration on dialysisresistant hypertension was not consistent. Normalization of blood pressure was observed in three out of six hypertensive patients with a decrease in plasma renin activity. Hemofiltration seemed to have favorable effects on secondary hyperparathyroidism and hyperphosphatemia. In order to test the hypothesis that hemofiltration resulted in transport of fluid and solutes from the intracellular to the extracellular, and thence to the ultrafiltrate compartment, the urea concentration of total effluent, serum, and cerebrospinal fluid were measured during hemofiltration and hemodialysis. While the total amount of urea removed was comparable between hemofiltration and hemodialysis on a small dialyzer, during hemofiltration the decay curve of the serum urea concentration was more delayed and urea in the cerebrospinal fluid was more efficiently removed than in hemodialysis. We conclude that, compared with hemodialysis, hemofiltration gives rise to less decrease of plasma osmolality and circulating plasma volume without red cell swelling, better compensation of acidosis despite less infusion of acetate to the patients, and less paradoxical acidosis in cerebrospinal fluid with a lower urea concentration gradient between cerebrospinal fluid and plasma. These findings may explain the significantly lower incidence of dialysis disequilibrium syndrome observed during hemofiltration.