Two-in-One Protocol: Simultaneous Small-Pore and Ultrasmall-Pore Peritoneal Transport Quantification

Abstract

Background

Reduced free water transport (FWT) through ultrasmall pores contributes to net ultrafiltration failure (UFF) and should be seen as a sign of more severe functional deterioration of the peritoneal membrane. The modified peritoneal equilibration test (PET), measuring the dip in dialysate Na concentration, estimates only FWT. Our aim was to simultaneously quantify small-solute transport, FWT, and small-pore ultrafiltration (SPUF) during a single PET procedure.

Methods

We performed a 4-hour, 3.86% glucose PET, with additional measurement of ultrafiltration (UF) at 60 minutes, in 70 peritoneal dialysis patients (mean age: 50 ± 16 years; 61% women; PD vintage: 26 ± 23 months). We calculated the dialysate-to-plasma ratios (D/P) of creatinine and Na at 0 and 60 minutes, and the Na dip (Dip_D/PNa60,), the delta dialysate Na 0–60 (ΔDNa_0–60), FWT, and SPUF.

Results

Sodium sieving (as measured by ΔDNa_0–60) correlated strongly with the corrected Dip_D/PNa60, (r = 0.85, p < 0.0001) and the corrected FWT (r = 0.41, p = 0.005). Total UF showed better correlation with FWT than with indirect measurements of Na sieving (r = 0.46, p < 0.0001 for FWT; r = 0.360, p < 0.0001 for Dip_D/PNa60,). Corrected FWT fraction was 0.45 ± 0.16. A negative correlation was found between time on PD and both total UF and FWT (r = -0.253, p = 0.035 and r = -0.272, p = 0.023 respectively). The 11 patients (15.7%) diagnosed with UFF had lower FWT (89 mL vs 164 mL, p < 0.05) and higher D/P creatinine (0.75 vs 0.70, p < 0.05) than did the group with normal UF. The SPUF correlated positively with FWT in the normal UF group, but negatively in UFF patients (r = -0.709, p = 0.015). Among UFF patients on PD for a longer period, 44.4% had a FWT percentage below 45%.

Conclusions

Measurement of FWT and SPUF is feasible by simultaneous quantification during a modified 3.86% glucose PET, and FWT is a decisive parameter for detecting causes of UFF in addition to increased effective capillary surface.

Keywords

Peritoneal equilibration test aquaporins peritoneal transport ultrafiltration failure

Get full access to this article

View all access options for this article.

References

Heimbürger

, Waniewski

, Werynski

, Tranæus

, Lindholm

Peritoneal transport in CAPD patients with permanent loss of ultrafiltration capacity.

Kidney Int 1990; 38: 495–506.

Krediet

R.T.

, Imholz

A.L.

, Struijk

D.G.

, Koomen

G.C.

, Arisz

Ultrafiltration failure in continuous ambulatory peritoneal dialysis.

Perit Dial Int 1993; 13(Suppl 2): S59–66.

Selgas

, Bajo

M.A.

, Castro

M.J.

, del Peso

, Aguilera

, Fernández-Perpén

Risk factors responsible for ultrafiltration failure in early stages of peritoneal dialysis.

Perit Dial Int 2000; 20: 631–6.

Monquil

M.C.

, Imholz

A.L.

, Struijk

D.G.

, Krediet

R.T.

Does impaired transcellular water transport contribute to net ultrafiltration failure during CAPD?

Perit Dial Int 1995; 15: 42–8.

Ho-dac-Pannekeet

M.M.

, Atasever

, Struijk

D.G.

, Krediet

R.T.

Analysis of ultrafiltration failure in peritoneal dialysis patients by means of standard peritoneal permeability analysis.

Perit Dial Int 1997; 17: 144–50.

Krediet

R.T.

, Lindholm

, Rippe

Pathophysiology of peritoneal membrane failure.

Perit Dial Int 2000; 20(Suppl 4): S22–42.

Rippe

, de Arteaga

, Venturoli

Aquaporins are unlikely to be affected in marked ultrafiltration failure: results from a computer simulation.

Perit Dial Int 2001; 21(Suppl 3): S30–4.

La Milia

, Di Filippo

, Crepaldi

, Del Vecchio

, Dell'Oro

, Andrulli

Mini-peritoneal equilibration test: a simple and fast method to assess free water and small solute transport across the peritoneal membrane.

Kidney Int 2005; 68: 840–6.

Smit

, Struijk

D.G.

, Ho-Dac-Pannekeet

M.M.

, Krediet

R.T.

Quantification of free water transport in peritoneal dialysis.

Kidney Int 2004; 66: 849–54.

10.

Venturoli

, Rippe

Validation by computer simulation of two indirect methods for quantification of free water transport in peritoneal dialysis.

Perit Dial Int 2005; 25: 77–84.

11.

Rodrigues

A.S.

, Silva

, Bravo

, Oliveira

J.C.

, Fonseca

, Cabrita

Peritoneal membrane evaluation in routine clinical practice.

Blood Purif 2007; 25: 497–504.

12.

Cnossen

T.T.

, Smit

, Konings

C.J.

, Kooman

J.P.

, Leunissen

K.M.

, Krediet

R.T.

Quantification of free water transport during the peritoneal equilibration test.

Perit Dial Int 2009; 29: 523–7.

13.

van Biesen

, Heimbürger

, Krediet

, Rippe

, La Milia

, Covic

Evaluation of peritoneal membrane characteristics: a clinical advice for prescription management by the ERBP working group.

Nephrol Dial transplant 2010; 25: 2052–62.

14.

Garred

L.J.

, Canud

, Farell

P.C.

A simple kinetic model for assessing peritoneal mass transfer in chronic ambulatory peritoneal dialysis.

ASAIO J 1983; 6: 131–7.

15.

Teixidó

, Cofan

, Borrás

, Bonet

, Bonal

, Galimany

Mass transfer coefficient: comparison between methods.

Perit Dial Int 1993; 13(Suppl 2): S47–9.

16.

Zweers

M.M.

, Imholz

A.L.

, Struijk

D.G.

, Krediet

R.T.

Correction of sodium sieving for diffusion from the circulation.

Adv Perit Dial 1999; 15: 65–72.

17.

Westra

W.M.

, Smit

, Zweers

M.M.

, Struijk

D.G.

, Krediet

R.T.

Diffusion correction of sodium sieving applicable in a peritoneal equilibration test.

Adv Perit Dial 2003; 19: 6–9.

18.

Twardowski

Z.J.

, Nolph

K.D.

, Khanna

, Prowant

B.F.

, Ryan

L.P.

, Moore

H.L.

Peritoneal equilibration test.

Perit Dial Bull 1987; 7: 138–47.

19.

Parikova

, Smit

, Struijk

D.G.

, Zweers

M.M.

, Krediet

R.T.

The contribution of free water transport and small pore transport to the total fluid removal in peritoneal dialysis.

Kidney Int 2005; 68: 1849–56.

20.

Waniewski

, Debowska

, Lindholm

Water and solute transport through different types of pores in peritoneal membrane in CAPD patients with ultrafiltration failure.

Perit Dial Int 2009; 29: 664–9.

21.

Waniewski

, Debowska

, Lindholm

Ultrafiltration and absorption in evaluating aquaporin function from peritoneal transport of sodium.

Perit Dial Int 2007; 27: 687–90.

22.

Asghar

R.B.

, Davies

S.J.

Pathways of fluid transport and reabsorption across the peritoneal membrane.

Kidney Int 2008; 73: 1048–53.

23.

Parikova

, Smit

, Struijk

D.G.

, Krediet

R.T.

Analysis of fluid transport pathways and their determinants in peritoneal dialysis patients with ultrafiltration failure.

Kidney Int 2006; 70: 1988–94.

24.

Rippe

, Venturoli

Simulations of osmotic ultrafiltration failure in CAPD using a serial three-pore membrane/ fiber matrix model.

Am J Physiol renal Physiol 2007; 292: F1035–43.

25.

La Milia

, Limardo

, Virga

, Crepaldi

, Locatelli

Simultaneous measurement of peritoneal glucose and free water osmotic conductances.

Kidney Int 2007; 72: 643–50.

26.

Krediet

R.T.

The effective lymphatic absorption rate is an accurate and useful concept in the physiology of peritoneal dialysis.

Perit Dial Int 2004; 24: 309–13.

27.

Waniewski

, Debowska

, Lindholm

How accurate is the description of transport kinetics in peritoneal dialysis according to different versions of the three-pore model?

Perit Dial Int 2008; 28: 53–60.

28.

Waniewski

, Sobiecka

, Debowska

, Heimbürger

, Weryński

, Lindholm

Fluid and solute transport in CAPD patients before and after permanent loss of ultra-filtration capacity.

Int J Artif organs 2005; 28: 976–86.

29.

Smit

, Parikova

, Struijk

D.G.

, Krediet

R.T.

The difference in causes of early and late ultrafiltration failure in peritoneal dialysis.

Perit Dial Int 2005; 25(Suppl 3): S41–5.