Overview

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.

Eligibility

Inclusion Criteria:

• Age > 18 years
• The patient was hospitalized in the intensive care unit of Amiens-Picardie University Hospital.
• Patient with an increase in fluid balance (TBW > 5%)
• Patient receiving continuous veno-venous hemofiltration (CVVH) on a PrismaFlexR or PrisMaxR machine, initiated due to oliguria, potassium level > 6.5 mmol/L, urea level > 25 mmol/L, or creatinine > 300 µmol/L and severe metabolic acidosis (pH < 7.2).
• Hemodynamically stable patient with a mean arterial pressure (MAP) > 65 mmHg for more than 4 hours with norepinephrine.
• Signed consent to participate in the study by the patient or, if unconscious, their legal representative/next of kin.

Exclusion Criteria:

• Invalid BIA measurements
• Internal device powered by an electrical current (pacemaker, implantable cardioverter-defibrillator, neurostimulator)
• Cardiac arrhythmia (atrial fibrillation, atrial flutter) present at the inclusion
• Chronic dialysis patient
• Moribund patient
• The patient is on extracorporeal mechanical support
• Hemorrhagic shock
• Pregnant woman
• Patient under guardianship or conservators.