title: Calcium balance in pediatric online hemodiafiltration: Beware of sodium and bicarbonate in the dialysate.
abstract: BACKGROUND
  Online hemodiafiltration (oHDF) is increasingly used in children; we treated 28 children since 2009, adapting this technique to pediatric patients.
  
  
  METHODS
  In this service evaluation audit, we assessed plasma electrolytes to evaluate the evolution of total (tCa) and ionized (iCa) during a session, as well as dialysate calcium (dCa) concentrations.
  
  
  RESULTS
  Using a 1.25 mmol Ca/L-dialysate, both tCa and iCa decreased during the session, with iCa falling below 1.1 mmol/L in 4/5 patients. In contrast, using a 1.5 mmol Ca/L-dialysate, iCa remained normal in all patients. Major discrepancies were observed between the expected and the measured dCa: 1.25 vs. 1.01 (0.83-1.04), and 1.5 vs. 1.47 (0.85-1.75) mmol/L, respectively (results presented as median [range]). These differences were explained by the modality of reconstituting dialysate: increasing bicarbonates and/or decreasing sodium requested in the dialysate decreases calcium extraction from the acid preparation. Proof of concept was given when requesting in an "ex-vivo" setting modifications in the requested sodium and bicarbonate in dialysate directly on the Fresenius machine.
  
  
  CONCLUSIONS
  Nephrologists should be aware that "high bicarbonate and/or low sodium" requirements in oHDF decrease calcium in the dialysate.
authors.affiliation: Centre de référence des maladies rénales rares, hôpital Femme-Mère-Enfant, 59, boulevard Pinel, 69677 Bron cedex, France; Université de Lyon, 69008 Bron, France. Electronic address: justine.bacchetta@chu-lyon.fr.
authors.forename: Justine
authors.initials: J
authors.lastname: Bacchetta
authors.affiliation: Centre de référence des maladies rénales rares, hôpital Femme-Mère-Enfant, 59, boulevard Pinel, 69677 Bron cedex, France.
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Sellier-Leclerc
authors.affiliation: Centre de référence des maladies rénales rares, hôpital Femme-Mère-Enfant, 59, boulevard Pinel, 69677 Bron cedex, France.
authors.forename: Aurélia
authors.initials: A
authors.lastname: Bertholet-Thomas
authors.affiliation: Département de biologie, hospices civils de Lyon, 69677 France.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Carlier
authors.affiliation: Département de biologie, hospices civils de Lyon, 69677 France.
authors.forename: Régine
authors.initials: R
authors.lastname: Cartier
authors.affiliation: Centre de référence des maladies rénales rares, hôpital Femme-Mère-Enfant, 59, boulevard Pinel, 69677 Bron cedex, France; Université de Lyon, 69008 Bron, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Cochat
authors.affiliation: Centre de référence des maladies rénales rares, hôpital Femme-Mère-Enfant, 59, boulevard Pinel, 69677 Bron cedex, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Ranchin
mesh_terms: D000293:Adolescent; D001639:Bicarbonates / Q000032:analysis*; D002118:Calcium / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D005260:Female; D017583:Hemodiafiltration / Q000379:methods*; D015312:Hemodialysis Solutions / Q000737:chemistry*; D006801:Humans; D008297:Male; D010372:Pediatrics; D012189:Retrospective Studies; D012964:Sodium / Q000032:analysis*
chemical_list: D001639:Bicarbonates; D015312:Hemodialysis Solutions; D012964:Sodium; D002118:Calcium
keywords: Bicarbonates; Calcium; Online hemodiafiltration; Pediatrics; Sodium