Whole-body single-frequency bioimpedance analysis in pediatric hemodialysis patients.

BACKGROUND: We hypothesized that the percent change in resistance (%RΔ) from bioimpedance analysis (BIA) measurements during hemodialysis (HD) can provide information on pediatric HD patients' hydration status. METHODS: Whole-body single-frequency BIA measurements were obtained before HD, each hour on HD, and after HD during two HD sessions. Pre-and post-HD weights, blood pressures, Crit-Line® measurements, and intradialytic symptoms were collected on the day of the BIA measurements. RESULTS: One hundred and thirty BIA measurements were obtained from 14 HD patients. The group was 43 % girls, and the mean age was 13.2 ± 4.4 years. Percent change in resistance was 13.5 ± 10.8 % at the end of HD; %RΔ correlated with percent body weight change (%BWΔ) following HD (r = -0.83, P < 0.01), as well as with percent blood volume change (%BVΔ) (r = -0.79, P < 0.01). The %RΔ was similar between patients with and without hypertension immediately before HD and was greater in those with intradialytic symptoms (19.1 ± 7.7 %) than in those without (9.9 ± 11.2 %) (P = 0.02). Patients with left ventricular hypertrophy (LVH) had lower %RΔ (7.2 ± 9.7 %) than those without (19.5 ± 7.7 %) (P = 0.03). Left ventricular mass index (LVMI) also correlated strongly with %RΔ (r = -0.79, P = 0.004) and %BWΔ (r = 0.82, P = 0.002). CONCLUSIONS: Our study showed that %RΔ strongly correlates with %BWΔ and %BVΔ and that %RΔ also correlated with intradialytic symptoms and LVMI.