Optimization of Fluid Balance Guided by Bioelectrical Impedance Analysis in Patients Undergoing Continuous Renal Replacement Therapy in Critical Care

In critical care, hemodynamic instability often requires volume expansion to restore tissue perfusion, increasing fluid balance and TBW, factors associated with higher mortality. Excess fluid leads to organ dysfunction due to venous congestion, making fluid removal crucial. When diuretics fail, RRT, typically through continuous renal replacement therapy (CRRT), is recommended. However, prescribing the correct level of UF is challenging; insufficient UF can worsen edema, while excessive UF risks hemodynamic instability. This pilot, single-center, prospective, interventional, randomized, controlled, open-label study includes two parallel groups: a standard group with UF prescribed by the physician based on clinical and hemodynamic status and an experimental group with UF guided by the extracellular to total body water (ECW/TBWat) ratio measured by BIA. The aim is to determine if ECW/TBW-guided UF improves fluid and TBW reduction over a 72-hour RRT period.