Effect of dialysate potassium and lactate on serum potassium and bicarbonate concentrations during daily hemodialysis at low dialysate flow rates

Abstract

Background Observational studies of hemodialysis patients treated thrice weekly have shown that serum and dialysate potassium and bicarbonate concentrations are associated with patient outcomes. The effect of more frequent hemodialysis on serum potassium and bicarbonate concentrations has rarely been studied, especially for treatments at low dialysate flow rate. Methods These post-hoc analyses evaluated data from patients who transferred from in-center hemodialysis (HD) to daily HD at low dialysate flow rates during the FREEDOM Study. The primary outcomes were the change in predialysis serum potassium and bicarbonate concentrations after transfer from in-center HD (mean during the last 3 months) to daily HD (mean during the first 3 months). Results After transfer from in-center HD to daily HD (data from 345 patients, 51 ± 15 years of age, mean ± standard deviation), predialysis serum potassium decreased ( P < 0.001) by approximately 0.4 mEq/L when dialysate potassium concentration during daily HD was 1 mEq/L; no change occurred when dialysate potassium concentration during daily HD was 2 mEq/L. After transfer from in-center HD to daily HD (data from 284 patients, 51 ± 15 years of age), predialysis serum bicarbonate concentration decreased ( P = 0.0022) by 1.0 ± 3.3 mEq/L when dialysate lactate concentration was 40 mEq/L but increased ( P < 0.001) by 2.5 ± 3.5 mEq/L when dialysate lactate concentration was 45 mEq/L. These relationships were dependent on serum potassium and bicarbonate concentrations during in-center HD. Conclusions Control of serum potassium and bicarbonate concentrations during daily HD at low dialysate flow rates is readily achievable; the choice of dialysate potassium and lactate concentration can be informed when transfer is from in-center HD to daily HD. Electronic supplementary material The online version of this article (10.1186/s12882-019-1450-7) contains supplementary material, which is available to authorized users.

Optimizing serum total carbon dioxide concentration during short and nocturnal frequent hemodialysis using lactate as dialysate buffer base

“…We recently demonstrated that the dialysate concentration of lactate can influence predialysis serum tCO 2 concentrations when patients are transferred from ICHD to daily home HD using the NxStage System One during the FREEDOM study 2 ; however, the treatments prescribed during that study were restricted to almost universally 20 to 25 L of dialysate volume for six treatments per week. Those findings, while noteworthy, may not be generalizable to today as current FHD treatment prescriptions are highly varied in clinical practice (internal data from NxStage Medical).…”

“…Clinical data analyzed in this study were collected during the FREEDOM study and were previously reported 2 . Predialysis serum tCO 2 concentrations were available from 284 patients who transferred from ICHD to daily home HD.…”

“…Clinical data analyzed in this study were collected during the FREEDOM study and were previously reported. 2 Predialysis serum tCO 2 concentrations were available from 284 patients who transferred from ICHD to daily home HD. During daily home HD, patients were treated using a mean of 22.1 L of lactate-containing dialysate per treatment, for a mean of 5.9 times per week.…”

“…In 104 patients from seven dialysis centers in four Western European countries, Cherukuri et al 1 showed that frequent home HD for 6 months resulted in an increase of serum bicarbonate concentration by 1 mEq/L; however, the prescribed dialysate lactate concentrations were not reported. In a retrospective cross‐sectional study of 284 patients who transferred from thrice‐weekly in‐center HD (ICHD) to daily home HD during the FREEDOM Study, Leypoldt et al 2 reported that daily home HD for 3 months resulted in a mean decrease of 1.0 mEq/L in serum tCO 2 concentration when using a dialysate lactate concentration of 40 mEq/L but a mean increase of 2.5 mEq/L when using a dialysate lactate concentration of 45 mEq/L. Very recently, Gangaram et al 3 reported biochemical data on 20 patients from four dialysis centers in Europe treated by nocturnal home HD using the NxStage System One.…”

“…The current work examined the data from the study of Leypoldt et al 2 using the H + mobilization model recently described by Sargent et al 4 In these analyses, we first calculated the hydrogen ion or acid generation rate for sub‐groups of HD patients using a weekly mass balance analysis of the H + mobilization model 5 . Based on those acid generation rates, we then predicted the effect of different lactate‐containing dialysis solutions on serum acid–base control for patients treated by short and nocturnal frequent HD with a variety of treatment frequencies, dialysate volumes per treatment, and treatment times.…”