The benefits and side effects of ramped hypertonic sodium dialysis

The effectiveness of ramped hypertonic sodium dialysis (RHSD) is controversial because of the prevalence of side effects (weight gain and hypertension). Standard dialysis (SD) was therefore compared with RHSD in a double-blind controlled crossover trial. Eleven patients who suffered from symptoms attributable to water shifts from extracellular fluid to intracellular fluid (headaches or hangover) or extracellular-fluid volume contraction (cramps or lightheadedness) and five asymptomatic patients were enrolled in the study. RHSD was individually tailored to each patient (to minimize thirst) during a 2-wk run-in period. Patients then received RHSD and SD for a period of 3 wk in randomized sequence. Outcome measures were both objective and subjective ratings on questionnaires. Significant differences were found between the two treatments, with RHSD improving specific problems (70% of lightheadedness/cramps, 100% of headaches/hangover) versus SD. Weight gain and hypertension were not different between the two treatments despite increased thirst sensation reported by 14/16.94% of patients preferred RHSD. Long-term studies in 20 different patients demonstrated the lack of increase in blood pressure or weight gain after 3 and 6 months of therapy.