Article Text
Abstract
Background and aim Knowledge of fluid compartment changes and nutritional status is crucial when evaluating critically ill children, as well as measuring the effect of treatment.
Current reference methods (DXA, dilution-methods etc.) are invasive, expensive, and/or time consuming and are therefore not suitable for routine paediatric examination.
Bioimpedance analysis (BIA) offers an alternative to this since it is non-invasive, simple, portable and inexpensive.
One BIA approach is to use values of total body fluid (TBF), extra- and intracellular fluid (ECF, ICF) and/or body cell mass (BCM). These are based on predictive equations and only proven in adults. Another approach is to use the phase angle (PA), which is a combination between the electrical resistance (R) of the electrolytic-containing TBF, and the capacitive reactance (XC) of the cell membrane, both expressed in ohms (Ω). PA is an indicator of fluid compartment changes and cell membrane properties.
Aim To investigate the relation between PA and weight (kg) and the body surface area, BSA (m2).
Methods Whole-body BIA was performed in 47 healthy children (boys=33, girls=14, 0–14 yr). PA (arctan = XC/R, degrees) was measured at 50-kHz with a bioimpedance spectroscopy device (Xitron 4200). Statistics: Spearman’s rank correlation (r), p < 0.05 and a 95% confidence interval.
Conclusions PA offers promising perspectives for further research areas (e.g. gender influence on PA). Potentially, PA could be a new way of monitoring fluid compartment changes and nutritional status in critically ill children.