title: Ionic mass balance and blood volume preservation during a high, standard, and individualized dialysate sodium concentration.
abstract: BACKGROUND
  Although a higher dialysate sodium concentration (DNa) is frequently used to improve haemodynamic stability during haemodialysis, few studies have compared ionic mass balance (IMB) during different DNa. Moreover, DNa is usually a standard prescription, whereas inter-individual pre-dialytic serum sodium levels may differ widely. The aims of the study were to assess IMB and the decline in blood volume (DeltaBV) during isovolaemic HD as well as during HD combined with ultrafiltration (UF) during DNa [140], DNa [144], and an individualized DNa [ind], in which DNa is equal to pre-HD plasma conductivity x 10.
  
  
  METHODS
  IMB and plasma conductivity were assessed by on-line conductivity measurements (Diascan; Hospal) in 13 HD patients. After 1 h of isovolaemic HD, measurements were continued during UF+HD until dry weight. DeltaBV was assessed by an optical method (Hemoscan).
  
  
  RESULTS
  During isovolaemic HD with DNa [140] and [144], Pre-Na was significantly related to IMB (r=0.83 and r=0.61; P<0.05). Diffusive Na flux into the patient occurred when the difference between DNa and pre-dialytic serum sodium was larger than 5 mmol/l. During UF+HD, IMB was 318+/-166 mmol during DNa [140], 277+/-116 mmol during DNa [ind], and 239+/-111 during DNa [144] (mean+/-SD; P<0.05 compared with the other treatment modalities) whereas DeltaBV did not differ significantly. In the five patients with a pre-dialytic sodium concentration below 140 mmol/l, ionic removal was significantly higher during DNa [ind] (324+/-87) compared with DNa [140] (228+/-127 mmol; P<0.05) without a significant difference in DeltaBV (-9.7+/-1.6 vs -7.8+/-2.3%).
  
  
  CONCLUSIONS
  A large difference in IMB was observed between DNa 144 and DNa 140, without a significant difference in DeltaBV. In patients with low pre-dialytic serum sodium levels, diffusive ionic influx from the dialysate into the patient may occur. In patients with low pre-dialytic sodium levels, DNa [ind] leads to an enhanced ionic removal compared with DNa [140] without large differences in DeltaBV.
authors.affiliation: St Joseph Hospital, Veldhoven and. University Hospital, Maastricht, The Netherlands.
authors.forename: Karin
authors.initials: K
authors.lastname: Moret
authors.forename: Daxenos
authors.initials: D
authors.lastname: Hassell
authors.forename: Jeroen P
authors.initials: JP
authors.lastname: Kooman
authors.forename: Frank
authors.initials: F
authors.lastname: van der Sande
authors.forename: Paul G G
authors.initials: PG
authors.lastname: Gerlag
authors.forename: A Warmold L
authors.initials: AW
authors.lastname: van den Wall Bake
authors.forename: Jarno
authors.initials: J
authors.lastname: van de Bogaart
authors.forename: Karel M L
authors.initials: KM
authors.lastname: Leunissen
mesh_terms: D000368:Aged; D001810:Blood Volume / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D006435:Renal Dialysis / Q000379:methods*; D015203:Reproducibility of Results; D012964:Sodium / Q000097:blood*; D014462:Ultrafiltration; D014882:Water-Electrolyte Balance
chemical_list: D012964:Sodium