Erythrocyte sodium-potassium activities, plasma natriuretic activity, and peripheral vascular resistances during hemodialysis or hemofiltration.

The effect of hemodialysis (acetate buffer) or hemofiltration on blood pressure, heart rate, peripheral vascular resistances, red blood cells ionic fluxes, and plasma natriuretic activity has been studied in six male patients treated for end-stage renal disease. The hemodynamic response to these two modes of treatment markedly differs. Whereas, peripheral resistances increase and heart rate is not affected during hemofiltration, a decrease in blood pressure, tachycardia, and vasodilation is observed during hemodialysis. However, in both therapeutic approaches, red blood cell ouabain-sensitive sodium-potassium pump activity increases in a similar way, and the plasmatic natriuretic activity decreases, whereas the vascular response to norepinephrine is reduced. All of these changes were strongly correlated to the amount of fluid removed. The natriuretic activity may thus play a role in the regulation of blood pressure and hemodynamic adjustments to fluid removal in chronic renal failure between two dialyses, but its action is not predominant during the dialysis session itself.