Contributions of Volume Overload Level and Ultrafiltration to Morbidity in ESKD - Project Summary/Abstract The long-term goal of this proposal is to modernize clinical methods for assessing fluid excess for removal during in-center hemodialysis treatment using newer assessment techniques. The experience of trial-and-error assessment of a “dry weight,” a weight at which a patient can tolerate fluid removal without the development of symptoms of hypovolemia or hypervolemia, a common practice for over 50 years, that may have a lasting effect on the ability to function for nearly 500,000 Americans who depend on hemodialysis for survival. Newer techniques for quantifying excess extracellular volume for removal during hemodialysis do exist. Small studies have suggested the potential utility of multi-frequency bioelectrical impedance spectroscopy (BIS) as a means to improve on clinical dry weight estimates to guide intradialytic ultrafiltration. Moreover, the rate at which fluid is removed during hemodialysis has been limited to not exceed 13ml//kg/hr based on observational studies on mortality. However, this association may differ relative to an individual's body size and may be more of a reflection of persistent volume overload rather than the just the rate of removal itself. The crude imprecise practice of dry weight assessment together with limitations in ultrafiltration rate may contribute to adverse patient experiences including persistent volume overload with peripheral edema and dyspnea on one hand, and intradialytic hypotension, fatigue, and muscle cramping on the other. Dialysis treatment day BIS estimation of excess extracellular fluid to direct ultrafiltration has the potential to improve patient-centered outcomes, the overarching premise of this proposal. We will gather evidence on the potential utility of BIS to improve the patient experience immediately following and during the post dialysis period. Our findings will inform future studies testing whether use of BIS to guide fluid removal during dialysis can improve how patients feel, function, and survive. We propose to compare dry weight estimation by BIS to usual care including estimate discordance on patient centered outcomes (Aim 1). We will also quantify the relative impact of high ultrafiltration rate and achievement (or non-achievement) of BIS-estimated target weight on patient physical function, sleep and quality of life (Aim 2) and examine clinical decision-making and patient perspectives on how UF management influences patients' dialysis experience using qualitative methods (Aim 3) among adults receiving hemodialysis in two metropolitan areas. The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) and the Kidney Disease Improving Global Outcomes (KDIGO) organizations are actively examining patient centered ways to improve care quality, the proposed work aligns with these efforts.