Solute Removal Characteristics of Continuous Recirculating Peritoneal Dialysis in Experimental and Clinical Studies

Abstract

Continuous recirculating peritoneal dialysis (CRPD) was introduced to enhance solute removal efficiency in conventional peritoneal dialysis (PD) therapies such as continuous ambulatory peritoneal dialysis (CAPD). In CRPD, a portion of the dwell dialysate in the patient's peritoneal cavity is drained through a double-lumen catheter and purified by an extracorporeal dialyzer. In this study, solute removal characteristics and safety of CRPD are examined in ex vivo and clinical studies. Recirculation dialysis experiments using nine dogs (13.6 +/- 2.5 kg of body weight) were carried out for 240 min in the ex vivo study, whereas another seven dogs (12.1 +/- 2.8 kg) received conventional peritoneal dialysis (CPD) (120 min dwelling x 2) and six additional dogs (11.9 +/- 2.7 kg) received a Tidal PD (20 min dwelling x 12; 50% of tidal volume ratio) as controls. The ex vivo study revealed that CRPD has a higher efficiency for solute removal than CPD and is equivalent to Tidal PD. In the BUN reduction rate, the 19.4 +/- 5.5% in 240 min CRPD (n = 9) was significantly higher (p< 0.05) than the 3.5 +/- 3.6% in 240 min CPD (n = 7) and equivalent to the 17.3 +/- 4.7% in 240 min Tidal PD (n = 6). Continuous recirculating peritoneal dialysis maintained a low UN level in the peritoneal cavity due to dialysis with an extracorporeal dialyzer. This tendency was also seen in creatinine removal. In the clinical study, CRPD (n = 10) and CPD (n = 5) treatments were used in three renal failure patients. Higher solute removal efficiency was shown in CRPD than in CPD treatments, and the urea peritoneal clearance was 14.1 +/- 4.4 ml/min in CRPD (n = 10), significantly higher (p < 0.05) than the 7.3 +/- 2.1 ml/min in CPD (n = 5). No fibrin formation occurred during CRPD treatments.

Interventional Nephrology and Dialysis: Continuous Flow Peritoneal Dialysis: Principles and Applications

“…Amerling et al (12) and Mineshima et al (20) have tried a simple side‐by‐side dual‐lumen catheter for CFPD. The “streaming” with this catheter is tremendous: more than 50% in our study.…”

Invited Editorial: New Concepts in Peritoneal Dialysis: New Wine in Old Barrels?

“…McKee et al (74) observed comparable clearances at different dialysate flow rates with one dual or with two separate dual lumen catheters in pig experiments. Mineshima et al (75) used a dual lumen catheter to perform CFPD in 10 patients. The obtained peritoneal urea clearance was 14.1 ± 4.4 ml/min in CFPD versus 7.3 ± 2.1 ml/min in the classic CCPD regimen.…”

Continuous Flow Peritoneal Dialysis: Is There a Need for it?

“…Recent studies have validated the kinetic constructs of CFPD and generated new enthusiasm for CFPD (32,36–38). Cruz et al (36) studied five patients with two separate catheters using fresh commercial dialysate with 1.5% dextrose, an exchange volume of 2 L, and a dialysate flow rate of 200 ml/min.…”

“…The differences most likely reflect the lower effective dialysate flow rate with the use of the single‐needle device. Mineshima et al (38) performed CFPD in clinical studies using a double‐lumen catheter, regeneration with a hemodialyzer, exchange volumes of 1 L, and peritoneal solution flow rates of only 100 ml/min. Once again their urea clearance averaged 14.1 ± 4.4 ml/min, which is better than with conventional PD, but much lower than the mean for CFPD.…”