Effects of on-line hemodiafiltration regimens and dialysate composition on serum concentrations of magnesium and calcium ions

Low-ionized magnesium and high-ionized calcium levels are associated with increased cardiovascular mortality in patients undergoing dialysis. We examined the effects of the dilution method, substitution volume, and dialysate of on-line hemodiafiltration on the total and ionized magnesium and calcium levels. Eighteen patients were randomly assigned to three dialysate groups: two acetic acid dialysate groups and one citrate dialysate group. Five treatment conditions were applied: pre-diluted on-line hemodiafiltration, post-diluted on-line hemodiafiltration, and hemodialysis. The total and ionized serum levels of magnesium and calcium were evaluated and found to be unaffected by the dilution methods and substitution volumes. The albumin leakage was approximately 3 g/session under the pre-dilution and hemodiafiltration conditions, and approximately 4–5 g/session under the post-dilution condition. The ionized magnesium concentration decreased in the citrate dialysate group. The on-line hemodiafiltration parameters had a negligible effect on ionized magnesium and calcium; however, the use of citrate dialysate decreased the ionized magnesium levels, probably because of chelation. 000028172 . The study was registered on July 11 2017.