title: The relationship between urine volume and drain volume as determinants of fractional urea clearance in continuous peritoneal dialysis.
abstract: A logistic regression model developed and validated in Albuquerque identified 24 hr urine volume (UV) and 24 hr drain volume/(body water) (DV/V) as predictors of fractional urea clearance (KT/V) in continuous peritoneal dialysis (CPD). Solution of this model provided DV/V values consistent with KT/V at least equal to a target KT/V for a given UV. The predictive accuracy of these unique DV/V values was tested in urea kinetic studies performed in 108 CPD patients in Thessaloniki and Athens with UV varying between 0 and 2 L/24 h. Two target weekly KT/V values, 1.70 and 1.90, were investigated. The equation DV/V = (5.2811-3.6996 UV)/ 17.554, derived by solving the logistic regression model, detected weekly KT/V > 1.70 (69/108, or 63.9% of the studies) with a sensitivity of 87.3% and a specificity of 60.4%. According to the same equation, the maximal UV consistent with weekly KT/V < or = 1.70 is 1.427 L/24 hr. The equation DV/V = (5.4994-2.6007 UV)/17.007 detected weekly KT/V > 1.90 (44/108, or 40.7% of the studies) with a sensitivity of 90.3% and a specificity of 79.2%. According to this equation, the maximal UV consistent with weekly KT/V < or = 1.90 is 2.115 L/24 hr. Determination of the lowest daily DV consistent with a target KT/V at any daily UV (within a wide range) is feasible in CPD.
authors.affiliation: Veterans Affairs Medical Center, Albuquerque, New Mexico 87108, USA.
authors.forename: A H
authors.initials: AH
authors.lastname: Tzamaloukas
authors.forename: G H
authors.initials: GH
authors.lastname: Murata
authors.forename: N V
authors.initials: NV
authors.lastname: Dombros
authors.forename: S
authors.initials: S
authors.lastname: Voudiklari
authors.forename: N
authors.initials: N
authors.lastname: Nicolopoulou
authors.forename: A
authors.initials: A
authors.lastname: Dimitriadis
authors.forename: E V
authors.initials: EV
authors.lastname: Balaskas
authors.forename: J
authors.initials: J
authors.lastname: Kakavas
authors.forename: E
authors.initials: E
authors.lastname: Batzili
authors.forename: S
authors.initials: S
authors.lastname: Antoniou
mesh_terms: D005240:Feasibility Studies; D006801:Humans; D007700:Kinetics; D010530:Peritoneal Dialysis / Q000592:standards*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D014508:Urea / Q000652:urine*; D016482:Urinalysis
chemical_list: D014508:Urea