What is the recommended dosage for peritoneal dialysis in adults?

Peritoneal Dialysis Dosing in Adults

For adults initiating peritoneal dialysis, prescribe based on body surface area (BSA) and residual kidney function, targeting a weekly Kt/V of at least 2.0, with exchange volumes of 2.0-3.0 L per cycle depending on BSA, using 4 exchanges daily for CAPD or 9-10 hours nightly for automated PD with daytime dwells. 1

Initial Prescription Based on Residual Kidney Function

Patients with GFR < 2 mL/min (Minimal Residual Function)

For CAPD (Continuous Ambulatory Peritoneal Dialysis): 1

• BSA < 1.7 m²: 2.0 L per exchange, 4 exchanges daily 1
• BSA 1.7-2.0 m²: 2.5 L per exchange, 4 exchanges daily 1
• BSA > 2.0 m²: 3.0 L per exchange, 4 exchanges daily 1

For CCPD (Continuous Cycling Peritoneal Dialysis): 1

• BSA < 1.7 m²: 2.0 L cycles for 9 hours nightly + 2.0 L daytime dwell 1
• BSA 1.7-2.0 m²: 2.5 L cycles for 9 hours nightly + 2.0 L daytime dwell 1
• BSA > 2.0 m²: 3.0 L cycles for 9 hours nightly + 3.0 L daytime dwell 1

Patients with GFR ≥ 2 mL/min (Significant Residual Function)

Incremental PD approach is appropriate, starting with 1-2 exchanges daily and increasing as residual function declines. 1, 2

For CAPD: 1

• BSA < 1.7 m²: 2.5 L per exchange, 3 exchanges daily 1
• BSA 1.7-2.0 m²: 3.0 L per exchange, 3 exchanges daily 1
• BSA > 2.0 m²: 3.0 L per exchange, 4 exchanges daily 1

For CCPD: 1

• BSA < 1.7 m²: 2.5 L cycles for 9 hours nightly + 2.0 L daytime dwell 1
• BSA 1.7-2.0 m²: 3.0 L cycles for 9 hours nightly + 2.5 L daytime dwell 1
• BSA > 2.0 m²: 3.0 L cycles for 10 hours nightly + 3.0 L daytime dwell 1

Target Adequacy Goals

The minimum target is a weekly Kt/V of 2.0, combining both peritoneal clearance (Kpt/V) and residual kidney clearance (Krt/V). 1 This target is based on compelling outcome data showing improved morbidity and mortality at this threshold. 1

For anuric patients (no residual function), achieving Kt/V ≥ 2.0 requires the full prescription outlined above, and approximately 85% will need daytime dwells in addition to nocturnal automated PD. 1

Urgent Start Protocol (When Dialysis Cannot Be Delayed)

If PD must be initiated within 10 days of catheter placement, use low-volume supine exchanges to prevent leaks: 1

• Start with frequent exchanges of 1.0-1.5 L while supine 1, 2
• Gradually increase volume by 200-500 mL every 2-3 days if no leakage occurs 2
• Reach target volume of approximately 2.0 L per exchange by day 14 for average-sized adults 2

Ideally, wait 10-14 days after catheter placement before starting full-volume PD to allow healing and reduce leak risk. 1

Optimizing Clearance When Targets Are Not Met

When weekly Kt/V remains below 2.0 despite standard prescription, increase total dialysate volume by either: 3, 4

1. Increasing exchange volume: Moving from 2.0 L to 2.5-3.0 L per exchange significantly increases both Kt/V and creatinine clearance 3, 4

2. Increasing number of exchanges: For automated PD, increasing from 3 cycles (9.5 L total) to 5 cycles (14.5 L) or 7 cycles (19.5 L) over the same 9-hour period raises weekly Kt/V from approximately 1.68 to 2.03 to 2.28 respectively 3

3. Adding once-weekly hemodialysis: For anuric patients who cannot achieve targets with PD alone, combination therapy (5-6 days PD + 1 HD session weekly) increases weekly Kt/V from 1.55 to 2.27 and improves nutritional parameters 5

Critical Monitoring Requirements

Obtain baseline 24-hour urine collection for urea and creatinine clearance before starting PD to calculate residual kidney function. 1 This determines whether incremental or full-dose initiation is appropriate. 1

Measure delivered dose (Kt/V and creatinine clearance) within the first month and then every 4-6 months, or more frequently if residual function is declining. 1 Residual kidney function must be monitored closely with incremental approaches to ensure total clearance does not fall below target. 1

Inform patients at initiation that their prescription will require adjustment over time as residual function declines and that most automated PD patients will eventually need daytime dwells. 1

Common Pitfalls to Avoid

Do not use single nighttime automated PD without daytime dwells in anuric patients—this rarely achieves adequate clearance. 1 The NKF-KDOQI guidelines explicitly state that approximately 85% of automated PD patients require one or more daytime dwells. 1

Do not delay increasing the prescription when Kt/V falls below 2.0. 1 Patients become at increased risk for malnutrition and uremic complications once weekly Kt/V drops below this threshold. 1

Do not assume that peritoneal transport characteristics remain stable—perform peritoneal equilibration testing to guide prescription adjustments, especially when adequacy targets are not met. 1