Newer Peritoneal Dialysis Solutions
Newer biocompatible PD solutions with reduced glucose degradation products, neutral pH, bicarbonate buffer, and alternative osmotic agents (icodextrin, amino acids) should be used to preserve peritoneal membrane function and improve ultrafiltration, particularly for long-term PD patients and those with ultrafiltration failure.
Rationale for Biocompatible Solutions
The evidence strongly supports transitioning from conventional glucose-based solutions to newer formulations:
Conventional PD solutions are inherently toxic to the peritoneal membrane due to high glucose concentrations, glucose degradation products (GDPs), acidic pH, lactate buffer, and hyperosmolarity, which activate inflammatory, fibrogenic, and angiogenic pathways leading to progressive peritoneal fibrosis and vasculopathy 1, 2.
Chronic exposure to high-GDP conventional solutions causes increased peritoneal vascular density, elevated small-solute transport rates, decreased ultrafiltration capacity, and increased restriction to macromolecule transport—changes that worsen with dialysis vintage 3.
Newer biocompatible solutions with reduced GDPs, neutral pH, and bicarbonate buffer improve peritoneal membrane health and viability 4.
Specific Solution Components and Their Benefits
Icodextrin (Glucose Polymer)
Icodextrin is specifically indicated for long dwells to reduce glucose exposure and protect the peritoneal membrane from the damaging effects of hypertonic glucose solutions 3.
Icodextrin increases peritoneal ultrafiltration and decreases extracellular fluid volume, improving volume control without the membrane damage associated with hypertonic glucose 3.
Once-daily use of icodextrin (typically for the long daytime dwell in APD or overnight dwell in CAPD) lessens harmful glucose exposure while maintaining adequate ultrafiltration 4.
Bicarbonate Buffer
- Bicarbonate-buffered dialysate improves biocompatibility compared to lactate-buffered solutions and should be preferentially used 3.
Amino Acid Solutions
Amino acid-based solutions can be used once daily as an alternative osmotic agent to reduce glucose exposure while providing nutritional support 4.
Combined use of icodextrin and/or amino acid solutions once daily minimizes peritoneal membrane exposure to glucose 4.
Clinical Implementation Strategy
When to Use Newer Solutions
All long-term PD patients should have at least one exchange daily with icodextrin or amino acid solution to minimize glucose exposure 4.
Patients with ultrafiltration failure require icodextrin for the long dwell, as it maintains ultrafiltration through colloid osmosis independent of peritoneal transport characteristics 3.
High/rapid transporters benefit particularly from icodextrin during long dwells, as rapid glucose absorption in these patients eliminates the osmotic gradient with conventional glucose solutions 5.
Diabetic and glucose-intolerant patients should maximize use of non-glucose osmotic agents to avoid systemic hyperglycemia 2.
Prescription Framework
Use the lowest possible glucose concentration to achieve desired volume status, supplementing with icodextrin for the long dwell 5.
Reserve hypertonic glucose exchanges (3.86%/4.25%) only for patients requiring additional ultrafiltration beyond what icodextrin and lower glucose concentrations provide 5.
Monitor drain volumes monthly from the long dwell (overnight for CAPD, daytime for APD) to assess ultrafiltration adequacy and adjust solution osmotic agents accordingly 5.
Evidence Limitations and Real-World Considerations
Survival Data Gap
No definitive evidence exists that newer PD solutions improve patient survival compared to conventional solutions, though they clearly improve membrane preservation 4.
Clinical outcomes data after adjusting therapy based on peritoneal equilibration testing and using newer PD solutions remain lacking 5.
Practical Barriers
Newer PD solutions are not universally available in many countries, where conventional glucose-based solutions continue to have an established role despite their known negative features 4.
Cost considerations may limit access to biocompatible solutions in some healthcare systems, though PD remains significantly less expensive than hemodialysis overall 6, 7.
Common Pitfalls to Avoid
Do not use only conventional glucose solutions for all exchanges in long-term PD patients, as this accelerates peritoneal membrane damage 1, 2.
Do not delay introduction of icodextrin until ultrafiltration failure develops; use it proactively to prevent membrane deterioration 3.
Do not perform peritoneal transport testing within 1 month of peritonitis resolution, as transient inflammatory changes will overestimate transport rates and underestimate true membrane function 5.
Do not assume adequate clearance means adequate prescription—patients with minimal residual kidney function require dwells for the majority of 24 hours to optimize middle-molecule clearance, even when small-molecule targets are met 8.
Monitoring Strategy
Establish baseline peritoneal transport characteristics 4-8 weeks after starting PD to guide solution selection 5.
Repeat transport testing when ultrafiltration failure is suspected, using the modified 3.86%/4.25% dextrose PET to optimally evaluate membrane function 5.
Assess clinical volume status and drain volumes at each monthly visit rather than routine annual transport testing, as most patients maintain stable transport characteristics over time 5.