Will a patient on lactate-containing peritoneal dialysis (PD) fluid have elevated lactate levels?

Lactate Levels in Patients on Lactate-Containing Peritoneal Dialysis Fluid

Yes, patients on lactate-containing peritoneal dialysis fluid can have elevated serum lactate levels, though the clinical significance of this elevation differs from that in non-dialysis patients. 1, 2

Mechanism and Evidence

• Absorption of lactate: Peritoneal dialysis (PD) solutions commonly use lactate as a buffer (typically 35-45 mmol/L), which can be absorbed into the bloodstream during dialysis 3, 4

• Elevation patterns:

  • In stable PD patients, serum lactate levels are typically within normal range during routine care 5
  • However, during acute illness or intercurrent events, PD patients show a higher prevalence of elevated lactate (>2 mmol/L) - observed in 29% of emergency department visits 2
  • D-lactate specifically can be elevated up to 4-fold higher than controls in patients using D-lactate-containing PD fluids 6

• Energy contribution: Lactate from PD fluid provides 3.62 kcal/g and can contribute significant calories (115-1300 kcal/day) depending on the type and rate of fluids used 3

Clinical Implications

Interpretation of Elevated Lactate

• Different significance: Elevated lactate in PD patients does not carry the same prognostic significance as in the general population 2

• Not always indicating shock: In approximately 50% of PD patients with elevated lactate presenting to emergency departments, there were no signs of hemodynamic instability 2

• Misleading diagnostic trigger: Elevated lactate in PD patients rarely indicates bowel ischemia despite often triggering abdominal CT scans (46.2% of cases with elevated lactate underwent CT, but bowel ischemia was present in only 1 case) 2

Management Considerations

• Buffer selection:

  • Bicarbonate is preferred over lactate as buffer for dialysis fluids in patients with hemodynamic instability, lactic acidosis, or liver failure 1
  • Bicarbonate/lactate-buffered neutral PD fluid may have beneficial effects on peritoneal preservation 7

• Nutritional accounting:

  • The calories from lactate in PD fluid should be included when calculating total energy provision to avoid overfeeding 3
  • This is particularly important when using high lactate replacement fluids, which can provide substantial calories 3

Special Considerations

• Contraindications for lactate-buffered solutions:

  • Severe liver failure
  • Pre-existing lactic acidosis
  • Post-liver transplantation
  • Hemodynamic instability/shock 1, 4

• Monitoring: In patients using lactate-containing PD fluids who present with acute illness, lactate levels should be interpreted cautiously and not used as the sole indicator of tissue hypoperfusion 2

Remember that elevated lactate in PD patients during acute illness may reflect altered metabolism of absorbed lactate rather than tissue hypoxia, and unnecessary investigations based solely on lactate elevation should be avoided.