Bioimpedance and inferior vena cava diameter for assessment of dialysis dry weight.

It is essential to carry out a clinical assessment of dry body weight in dialysis-dependent children in order to develop a suitable dialysis prescription. Bioimpedance analysis and inferior vena cava diameter (IVCD) have been evaluated and utilized in adults as noninvasive parameters for the assessment of dry weight and extracellular volume. Since there are no data available for normal children, we performed a prospective study to establish reference standards for a pediatric population (111 females and 95 males, aged 6.8-16 years). We found strong correlations of both resistance and IVCD with age, height, weight, and, in particular, with body surface area. IVCD and resistance also correlated with each other. We also investigated 28 pediatric dialysis patients who showed growth retardation and delayed puberty. Applying age-related reference intervals to pediatric dialysis patients resulted in an underestimation of overhydration. The combination of both methods using body surface area-related reference limits with the clinical features of deviation of dry weight will serve as an adjunct to the assessment of post-dialysis dry weight.