Bioelectrical impedance spectroscopy (BIS) in young children with acute and semi-acute hydration disorders: potentials and limitations.

This study aimed to evaluate the feasibility and reliability of bioelectrical impedance spectroscopy in young children suffering of acute hydrational disorders. Whole body and segmental measurements were carried out in a group of 42 of children aged 4 to 147 months, using a BIS analyzer (Xitron 4000B). This phase of the study involved several hundred of BIS measurement, which showed the feasibility of using this technique in young children. Using the sweep mode and the modeling software provided for the manufacturer of the instrument, the resistance of the extracellular (RECW) and intracellular (RICW) compartment was calculated. Correlation coefficient (r) and technical error of measurement (TEM) were obtained from paired BIS measurements. RECW showed to be highly reproducible (r = 0.99), with a relatively low TEM (from 1 to 3.5%), across all segments. The reliability was markedly lower respect to RICW, which shows the potential application of BIS technique even in critically ill young child populations.