title: Dialysate bicarbonate variation in maintenance hemodiafiltration patients: Impact on serum bicarbonate, intradialytic hypotension and interdialytic weight gain.
abstract: The dialysate bicarbonate (DB) influences the acid-base balance in dialysis patients. Very low and high serum bicarbonate (SB) have been related with a higher mortality. Acid-base balance also has been associated with hemodynamic effects in these patients. The trial aim was to compare the effect of DB concentration variation on SB levels in maintenance hemodiafiltration (HDF) patients and the effect on intradialytic hypotension and interdialytic weight gain.
  
  
  
  A prospective study, with 9 months of follow-up, involving 93 patients, divided in two groups: group 1 and group 2 with a DB of 34 mmol/L and 30 mmol/L, respectively, with monitoring of pre and post HDF SB, intradialytic hypotension, and interdialytic weight gain.
  
  
  
  Pre dialysis SB was higher in group 1: median concentration of 22.7 mmol/L vs. 21.1 mmol/L (P < 0.001). Post dialysis SB levels were higher in group 1: median concentration of 28.0 mmol/L vs. 25.3 mmol/L (P < 0.001). Post dialysis SB in alkalotic range was only detected in group 1 (51.2% of the patients). No significant differences were detected in intradialytic hypotension rate [28.0 vs. 27.4 episodes per 1000 sessions in group 1 and 2, respectively, (P = 0.906)] or in average interdialytic weight gain [2.9% vs. 3.0% in group 1 and 2, respectively, (P = 0.710)].
  
  
  
  DB of 30 mmol/L appears to be associated with SB levels closer to physiological levels than 34 mmol/L. The bicarbonate dialysate, in the tested concentrations, did not appear to have a significant impact on intradialytic hypotension and interdialytic weight gain in maintenance HDF patients.
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.|Department of Nephrology, Centro Hospitalar de, Setúbal, Setúbal, Portugal.
authors.forename: Márcio
authors.initials: M
authors.lastname: Viegas
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.|Department of Nephrology, Centro Hospitalar de, Setúbal, Setúbal, Portugal.
authors.forename: Cristina
authors.initials: C
authors.lastname: Cândido
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.|Department of Nephrology, Centro Hospitalar de, Setúbal, Setúbal, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Felgueiras
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.|Department of Emergency, Hospital Garcia de, Orta, Almada, Portugal.
authors.forename: José
authors.initials: J
authors.lastname: Clemente
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.
authors.forename: Sara
authors.initials: S
authors.lastname: Barros
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.
authors.forename: Rostislav
authors.initials: R
authors.lastname: Farbota
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.
authors.forename: Filipa
authors.initials: F
authors.lastname: Vera
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.
authors.forename: Antero
authors.initials: A
authors.lastname: Matos
authors.affiliation: Hemodialysis Unit, Nephrocare, Montijo, Montijo, Portugal.
authors.forename: Francisco
authors.initials: F
authors.lastname: Sousa
mesh_terms: D000368:Aged; D001639:Bicarbonates / Q000378:metabolism*; D015314:Dialysis Solutions / Q000009:adverse effects*; D005260:Female; D017583:Hemodiafiltration / Q000009:adverse effects*; D006801:Humans; D007022:Hypotension / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects*; D015430:Weight Gain / Q000187:drug effects*
chemical_list: D001639:Bicarbonates; D015314:Dialysis Solutions
keywords: Acid-base balance; chronic kidney disease; dialysate bicarbonate; hemodiafiltration; serum bicarbonate