Kinetic Modeling of Incremental Ambulatory Peritoneal Dialysis Exchanges

Area of Science:

• Nephrology
• Renal Replacement Therapy
• Peritoneal Dialysis

Background:

• Incremental peritoneal dialysis (PD), a gradual introduction to dialysis, is infrequently reported.
• A key concern is whether incremental regimens achieve adequate urea clearance targets.
• This study models urea kinetic parameters for incremental PD across different membrane types.

Purpose of the Study:

• To determine if incremental peritoneal dialysis (PD) regimens can achieve target urea clearance (Kt/V).
• To evaluate urea kinetic modeling for various incremental PD prescriptions across all membrane transport types.
• To assess the impact of residual kidney function on incremental PD adequacy.

Main Methods:

• Utilized a modified 3-pore model for peritoneal transport simulations.
• Evaluated incremental manual continuous ambulatory PD (CAPD) exchanges with glucose and/or icodextrin.
• Calculated peritoneal urea clearance, added residual kidney clearance, and compared to Kt/V target of 1.7 for all 4 membrane types.

Main Results:

• Two exchanges/day met adequacy targets if GFR was 6 mL/min/1.73 m² across all membrane types.
• Three exchanges/day achieved Kt/V targets at GFR 4-5 mL/min/1.73 m² (high to low transporters).
• Higher tonicity solutions (2.5% glucose or icodextrin) were needed for some 3-exchange regimens.

Conclusions:

• Incremental CAPD regimens can achieve urea kinetic targets in most PD patients with residual kidney function.
• Incremental PD presents a less intrusive, better-accepted, and cost-effective initiation to chronic dialysis.
• The importance of intrinsic kidney function in incremental PD regimens is highlighted, necessitating careful monitoring.