The Effect of Bicarbonate Profiling in Dialysis Fluid on Phosphate Removal During Hemodialysis and Blood pH

The Effect of Bicarbonate Profiling in Dialysis Fluid on Phosphate Removal During Hemodialysis and Blood pH

Hyperphosphatemia is still an unresolved problem among hemodialysis patients and significantly increases the risk of death from cardiovascular diseases. Research to date has not answered the question of whether dialysate bicarbonate concentration profiling can improve phosphate removal and its concentration without negative impact on the acid-base balance. This study addressed this issue.

Twenty stable hemodialysis patients will enroll to a four-week study during which different dialysate bicarbonate concentration profiles will be used each week. Each patient will undergo the following profiles (one-week periods): Treatment A - stable dialysate bicarbonate concentration Dbic 35 mmol/L during the whole HD session, Treatment B - Dbic 35 mmol/L for the first two hours and Dbic 30 mmol/L for the next two hours and Treatment C - the opposite mid-HD change Dbic from 30 to 35 mmol/L and one week wash-out period between Treatment B and C. We will collect blood samples each hour during the session and one hour after HD completion.

Inclusion Criteria:

• stable general condition
• hemodialysis more than 3 months
• Dialysis 3 times a week/ 4 hours +/- 20 minutes
• Dialysis with arterio-venous fistulas
• bicarbonate titer before hemodialysis 22-24 mmol/l

Exclusion Criteria:

• diabetes mellitus
• cachexia
• inflamation processes
• usage of sevelamer last month
• utrafiltration during dialysis more than 2500 ml