Efficacy of peritoneal dialysis during infusion and drainage procedures.
BACKGROUND
Inadequate dialysis is still a major cause of technique failure in peritoneal dialysis (PD). Mathematical models provide the possibility of direct and precise assessment of peritoneal transport of urea and creatinine throughout the dwell and allow calculation of optimal schedules, dwell times, and predicted adequacy of a prescribed regimen. Kinetic modeling is particularly important for automated PD. If the effectiveness of uremic toxin removal that takes place during infusion and drainage of dialysis fluid is not taken into account, the predicted adequacy of the whole PD session may be underestimated. ♢


OBJECTIVE
To estimate the efficacy of urea and creatinine removal during the dialysis fluid exchange procedure. ♢


METHODS
17 patients treated with PD were included in the study. PD effectiveness during dialysate exchange was defined as the quotient k of removed amount of creatinine/BUN during the infusion and drainage of dialysate and during a dwell of the same duration as the dialysate exchange. ♢


RESULTS
The effectiveness of creatinine and urea removal was reduced during the exchange procedure (k(creat) = 0.68 ± 0.43 and k(BUN) = 0.87 ± 0.44) and differed between these 2 solutes (p = 0.0009). The k coefficients for urea and creatinine were well correlated (R(2) = 0.83). ♢


CONCLUSIONS
The effectiveness of peritoneal transport of creatinine and BUN during the inflow/outflow phase was relatively high compared to that during the same dwell time (68% and 87% respectively). This real effectiveness of the dialysate exchange procedure should be taken into account in the process of planning automated PD sessions, otherwise the predicted overall efficacy of creatinine and urea removal throughout the session may be underestimated. This underestimation is proportional to the number of dwells per day.
Baczyski
Daniel
D
Department of Internal Medicine, Nephrology and Dialysis Therapy, Military Institute of Medicine, Warsaw, Poland. dbaczynski@esculap.pl
Antosiewicz
Stefan
S
Waniewski
Jacek
J
Nowak
Zbigniew
Z
Wakowicz
Zofia
Z
D019540:Area Under Curve; D001331:Automation; D001692:Biological Transport; D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000493:pharmacokinetics; D015314:Dialysis Solutions / Q000493:pharmacokinetics / Q000627:therapeutic use; D004322:Drainage / Q000379:methods; D005260:Female; D005544:Forecasting; D006801:Humans; D007263:Infusions, Parenteral / Q000379:methods; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D008956:Models, Chemical; D010530:Peritoneal Dialysis / Q000379:methods* / Q000706:statistics & numerical data; D013997:Time Factors; D016896:Treatment Outcome; D014508:Urea / Q000493:pharmacokinetics
D015314:Dialysis Solutions; D014508:Urea; D003404:Creatinine