DIALYSATE SODIUM DELIVERY CAN ALTER CHRONIC BLOOD-PRESSURE MANAGEMENT

Low dialysate sodium concentrations can reduce postdialysis thirst and serum sodium activity, but patients typically experience dialysis hyp otension, fatigue, disequilibrium, and cramps, ''High-sodium'' hemodia lysis minimizes dialysis disequilibrium but increases the serum sodium activity of most patients. Programmed ''variable-sodium'' dialysis ca n minimize dialysis discomfort but may also alter the sodium kinetics from those of ''high-sodium'' dialysis, We designed a cross-over study with random order assignment to determine whether a ''variable-sodium '' dialysis program could reduce the blood pressure of dialysis patien ts without increasing dialysis morbidity, Dialysis with a dialysate so dium of 140 mEq/L was compared with dialysis with a programmed exponen tial decrease of dialysate sodium from 155 mEq/L to 135 mEq/L, Dialysa te sodium was then held constant at 135 mEq/L for the final half hour of dialysis, Eighteen patients completed the 7-month study, each recei ving 3.5 months of experimental and 3.5 months of standard therapy, Pr ogrammed ''variable-sodium'' dialysis resulted in a reduction in antih ypertensive drug use without alterations in predialysis blood pressure , interdialytic weight gain, ultrafiltration tolerance, or the frequen cy of symptomatic dialysis cramps or hypotension, Patients did, howeve r, have lower postdialysis standing blood pressures and higher postdia lysis target weights during programmed ''variable-sodium'' dialysis. ( C) 1997 by the National Kidney Foundation, Inc.