Minimizing the drainage period for continuous ambulatory peritoneal dialysis.

OBJECTIVES

To examine features of drainage flow and to determine whether the drainage period could be safely reduced in continuous ambulatory peritoneal dialysis (CAPD) patients.

DESIGN

Open nonrandomized prospective study in CAPD patients.

SETTING

The kidney center in a tertiary care university hospital.

PATIENTS

Fourteen CAPD patients with good catheter function.

INTERVENTIONS

Drainage flow pattern was studied using a 2-L dialysate. The drainage period was reduced from 28 minutes (mean) to 10 minutes throughout a short-term, 2-month study period and a long-term, 6-month study period for 10 patients.

MAIN OUTCOME MEASURES

Ultrafiltration volume, body weight, and peritoneal clearance.

RESULTS

A kinetics analysis of the drainage period and volume indicated a positive linear correlation with two different slopes: one for rapid drainage for the first 5-7 minutes and one for subsequent slow drainage. The effluent exceeded 80% in the former period. Ultrafiltration volume and body weight showed no change due to the reduction. Improved peritoneal clearance of small molecular substances could not be confirmed despite a 5% increase in the effective dialysis period. Nearly all patients were satisfied with the reduction and desired its continuation.

CONCLUSIONS

Ten minutes is a sufficient drainage period for most CAPD patients with a 2-L dialysate volume. This may possibly allow an increase in daily activities and an effective peritoneal membrane dialysate contact period.