Bioelectrical impedance analysis enables a rapid and safe assessment of body water. Conversely, high phase angle readings appear to be consistent with large quantities of intact cell membranes of skeletal muscle and body cell mass. Those with a BMI > 95th percentile are considered obese [24]. Since patients with advanced CKD usually exhibit abnormal water balance, this can result in inaccurate estimations of fat-free, edema-free body mass and fat mass [121]. At low frequencies, the membrane lipid content of the body cell mass compartment acts as a capacitor, which limits the flow to intracellular space only. However, a multi-center randomized-controlled trial including 50 patients with fluid overload of 15% or more as demonstrated by BIS comparing three methods of dry weight reduction showed a high (31%) rate of dialysis-related complications across all groups demonstrating the difficulty of fluid removal in the dialysis population.