title: Calcium profiling in hemodiafiltration: a new way to reduce the calcium overload risk without compromising cardiovascular stability.
abstract: BACKGROUND
  Low and high dialysate calcium (Ca²⁺) content may have positive and harmful effects depending on the considered pathological aspect: hemodynamic instability, cardiac arrhythmias, parathormone release, adynamic bone disease, cardio-vascular calcifications. We hypothesized that a time-profiled Ca²⁺ concentration would keep the cardiovascular advantages of high Ca²⁺ but would reduce the risk of calcium overload.
  
  
  METHODS
  A prospective, multicenter study using a particular hemodiafiltration technique that allows the profiling of electrolytes was designed. Patients (n = 22) underwent randomly a 3-week dialysis session with low and high constant dialysate Ca²⁺ (Ld(Ca,), 1.25 mM and Hd(Ca,), 2 mM) and profiled Ca²⁺ (Pd(Ca)), respectively. Plasma and spent dialysate Ca²⁺, systolic and diastolic arterial pressure (SAP, DAP) and QT interval corrected for heart rate (QTc) were analyzed.
  
  
  RESULTS
  Plasma Ca²⁺ concentration decreased in Ld(Ca), whereas it increased in Hd(Ca) and to a lesser extent, in Pd(Ca). Total amount of Ca²⁺ given to the patient in Pd(Ca) (15.5 ± 1.0 mmol) was higher than in Ld(Ca) (4.3 ± 1.6 mmol) but lower than in Hd(Ca) (21.9 ± 3.3 mmol). SAP and DAP decreased in Ld(Ca), whereas it was almost constant in both Hd(Ca) and Pd(Ca·). QTc significantly increased, up to critical values (>460 msec), only during Ld(Ca·).
  
  
  CONCLUSIONS
  Pd(Ca) seems to retain the advantages of high Ca²⁺ in terms of hemodynamic stability and modification of QTc while reducing the excessive positive calcium balance typical of dialysis with high Ca²⁺ content.
authors.affiliation: 3 Nephrology and Dialysis Unit, ASL 8, Quartu S. Elena - Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Severi
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Bolasco
authors.forename: Fabio
authors.initials: F
authors.lastname: Badiali
authors.forename: Gabriella
authors.initials: G
authors.lastname: Concas
authors.forename: Elena
authors.initials: E
authors.lastname: Mancini
authors.forename: Aurora
authors.initials: A
authors.lastname: Summa
authors.forename: Claudia
authors.initials: C
authors.lastname: Perazzini
authors.forename: Denis
authors.initials: D
authors.lastname: Steckiph
authors.forename: Leonardo
authors.initials: L
authors.lastname: Cagnoli
authors.forename: Antonio
authors.initials: A
authors.lastname: Santoro
mesh_terms: D000368:Aged; D002118:Calcium / Q000097:blood*; D015314:Dialysis Solutions; D005260:Female; D017583:Hemodiafiltration / Q000379:methods*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000628:therapy*; D008297:Male; D011446:Prospective Studies
chemical_list: D015314:Dialysis Solutions; D002118:Calcium