Related Experiment Video
Updated: Aug 24, 2026

Evaluation of Fluid Overload by Bioelectrical Impedance Vectorial Analysis
Published on: August 17, 2022
Best method for estimating urea volume of distribution: comparison of single pool variable volume kinetic modeling
1Division of Nephrology, William Beaumont Hospital, Royal Oak, Michigan 48073-6705, USA.
Abstract:
The urea volume of distribution (Vurea) is a key component of the Kt/V parameter calculated during urea kinetic modeling. The Vurea parameter has been approximated empirically using total body water (TBW) estimates derived from anthropometric formulas or measured by bioelectric impedance analysis (BIA). The author compared TBW values derived using various anthropometric formulas (Watson, Hume, Randall, Tzamaloukas, Chertow) and BIA to the Vurea parameter calculated using three point variable volume single pool urea kinetic modeling. A total of 127 chronic hemodialysis patients were studied (mean age 66 +/- 13 years; 42% female; 37% black; 47% diabetic). Agreement between anthropometric formulas, BIA, and Vurea values was assessed by linear regression and Bland Altman analyses. The closest correlations were obtained with the BIA (r = 0.972), Chertow (r = 0.917), and Tzamaloukas (r = 0.905) methods. When compared with Vurea, 95% confidence intervals by Bland Altman analysis were lowest with BIA (4L) and highest with the Watson method (8L). These results indicate that BIA best approximates Vurea in dialysis patients.
Related Concept Videos
One-Compartment Open Model: Wagner-Nelson and Loo Riegelman Method for ka Estimation
On...
Drug Dosing in Renal Diseases: Measurement of Glomerular Filtration Rate
One-Compartment Open Model: Urinary Excretion Data and Determination of k
Drug Dosing in Renal Diseases: Estimation of Glomerular Filtration Rate Based on Serum Creatinine Concentration
Measurement of Bioavailability: Pharmacokinetic Methods
One-Compartment Open Model for IV Bolus Administration: Estimation of Elimination Rate Constant, Half-Life and Volume of Distribution
