Nocturnal ultrafiltration profiles in patients on APD: Impact on fluid and solute transport

In order to prevent morbidity and mortality in peritoneal dialysis (PD), sodium and water balance as well as a minimal level of small-solute clearances are needed. The impact of three nocturnal peritoneal ultrafiltration (UF) profiles on UF and small solute clearance in patients on automated PD (APD) was studied: constant glucose concentration of 1.36% (flat) or modifying the glucose concentration of the heater bag (descendant: 3.86-1.36%; ascendant: 1.36-3.86%). Sixty-two patients were enrolled in the study and received each profile within a four- month period, thus serving as their own controls. UF was lower with the flat profile (367 +/- 420 ml; P<0.01), but no difference was seen between the two higher glucose concentration profiles. Peritoneal Kt/V (pKt/V) and peritoneal creatinine clearance (CrpC) showed statistically higher values from the descendant vs ascendant vs flat profiles (pKt/V: 1.54 +/- 0.30 vs 1.45 +/- 0.30 vs 1.38 +/- 0.27, and CrpC: 36.9 +/- 7.9 vs 33.5 +/- 7.48 vs 29.92 +/- 7.5 ml min(-1)). Multivariate analysis showed statistical significance for the following: in the intrasubject comparisons, the profile for pKt/V (F= 9.109, P<0.001) and CrpC (F= 11.697, P<0.001), and in the intersubjects comparisons, the effects of both gender (F= 14.334, P<0.01) for pKt/V and peritoneal permeability for both parameters (pKt/V: F= 4.37, P<0.05; CrpC: F= 11.697, P<0.001). In conclusion, the application of ascendant and descendant UF profiles in automated PD is feasible and results in better UF and small solute clearances, thus preventing inadequate dialysis and volume overload.