Continuous tidal peritoneal dialysis (CTPD) prescription and adequacy targets

NKF-DOQI guidelines suggest a Kt/V value of 2.1 and a creatinine clearance (CRCL) value of 63 L/1.73 m2 of body surface area per week as minimum targets in continuous cycling peritoneal dialysis (CCPD). Those targets are obtained by adapting the CAPD guidelines. The aim of our study was to verify the possibility of reaching the suggested targets with continuous tidal peritoneal dialysis (CTPD) and to check target modification in this automated treatment. Eight anuric patients underwent four consecutive CTPD sessions with increasing total prescribed volumes (17 L, 22 L, 27 L, and 32 L; night 9 h; fill 2.2 L; tidal 75%, day 2 dwells). The Kt/V increase was significant (P = 0.012), unlike that of CRCL, with larger volumes. Two patients did not reach target Kt/V, and four did not reach target CRCL. The volume normalized for 1.73 m2 corresponding to DOQI targets was 19.6 +/- 2.6 L for Kt/V and 20.2 +/- 2.4 for CRCL. The overall Kt/V was 2.29 +/- 0.66 and CRCL was 57.3 +/- 16.5 L/1.73 m2. CRCL/Kt/V overall ratio was 25.6 +/- 4.7 and significantly different from the target ratio (63/2.1 = 30, P < 0.001). The CRCL/Kt/V ratio showed a significant decrease with larger volumes (P = 0.001, linear trend P < 0.001). Adequacy targets can be reached only in some patients on CTPD even with high dialysis volumes. The changes in the CRCL/Kt/V ratio in relation to dialysis volume can be considered for adaptation and evaluation of adequacy targets in automated treatments.