Association between VExUS score and worsening renal function during diuretic therapy in the ICU

BACKGROUND: In intensive care unit (ICU) settings, venous excess ultrasound (VExUS) score has gained attention for predicting Acute Kidney Injury (AKI). This led to the identification that venous congestion via VExUS should prompt diuretic therapy. However, in acute heart failure (AHF), a share of the literature considers creatinine elevation as a sign of efficient decongestion. Thus, the relationship between VExUS, diuretic response, and renal outcomes remains unclear in ICU patients. METHODS: Secondary analysis of a prospective observational study conducted in a cardiovascular ICU (2019-2022). Adult patients with clinical signs of fluid overload receiving loop diuretic treatment were included. Patients were divided into two groups based on their highest VExUS score severity over 24 h: congestive (VExUS ≥ 2) versus non-congestive (VExUS < 2). The primary outcome was WRF at ICU discharge. Secondary outcomes included diuretic response parameters, hemoconcentration, and distinction between "pseudo-WRF" (WRF with hemoconcentration) and "true-WRF" (WRF without hemoconcentration). RESULTS: Seventy-seven patients were analyzed (37 with VExUS < 2, 40 with VExUS ≥ 2). WRF occurred in 14 patients (37.8%) in the non-congestive group versus 8 patients (20.0%) in the congestive group (p = 0.139). No significant differences were observed between groups for diuretic response parameters: loop diuretic-adjusted diuresis at 2 h (545 vs 600 mL/40 mg, p = 0.950), natriuresis (104 vs 93.0 mmol/L, p = 0.355), cumulative fluid removal (-685 vs -1141 mL, p = 0.895), or cumulative loop diuretic prescription (120 vs 100 mg, p = 0.303). Hemoconcentration rates were similar between groups (48.6% vs 32.5%, p = 0.226), as were pseudo-WRF rates (16.2% vs 7.5%, p = 0.241). CONCLUSIONS: In critically ill patients systematically treated with loop diuretics, VExUS score was not significantly associated with worsening renal function or diuretic response parameters. These preliminary findings suggest that larger studies may be needed to better understand the potential relationship between VExUS and renal outcomes in this patient population.