No abstract

Malnutrition is a common problem in children with end‐stage liver disease (ESLD), and accurate assessment of nutritional status is essential in managing these children. In a retrospective study, we compared nutritional assessment by anthropometry with that by body composition. We analyzed all consecutive measurements of total body potassium (TBK, n= 186) of children less than 3 years old with ESLD awaiting transplantation found in our database. The TBK values obtained by whole body counting of 40K were compared with reference TBK values of healthy children. The prevalence of malnutrition, as assessed by weight (weight Z score <−2) was 28%, which was significantly lower (chi‐square test, p < 0.0001) than the prevalence of malnutrition (76%) assessed by TBK (<90% of expected TBK for age). These results demonstrated that body weight underestimated the nutritional deficit and stressed the importance of measuring body composition as part of assessing nutritional status of children with ESLD.

We compared the whole body (WB) and segmental bioelectrical impedance analysis (BIA) methodologies in a group of healthy adults (n= 25). It has been suggested that the segmental methodology may overcome the difficulty in generating a single algorithm to predict total body water (TBW) in all groups whether healthy or not. We measured TBW, using D2O dilution, and WB and segmental BIA parameters. Cole‐Cole analysis was used to determine the impedance at the characteristic frequency (Zc). The correlation between TBW (by D2O dilution) and segmental BIA measures (multiple regression, r= 0.90, p < 0.001, SEE = 3.1 L) was not significantly higher than the correlation between TBW (D2O dilution) and WB BIA measures (simple regression, r= 0.85, p < 0.001, SEE = 3.6 L). Others have observed this “lack of improvement” in a group of healthy subjects. The true value of the segmental BIA methodology may lie in applications involving groups with altered distributions of segmental and compartmental fluid.

At low-intensity exercise, there is a small but significant loss in both TBW and ECW fluids, and the magnitude of these losses does not change throughout a 3-wk exercise program. At moderate levels of exercise intensity, there is a greater loss of both TBW and ECW fluids. However, the magnitudes of these losses decrease significantly during the 3-wk exercise program, thus demonstrating a training effect.