Early assessment of fluid tolerance (VExUS) and stroke volume (LVOT-VTI) to predict adverse outcomes in emergency department patients with suspected sepsis.

BACKGROUND: To determine if early Doppler ultrasound assessments of venous congestion with Venous Excess Ultrasound (VExUS) and stroke volume with left ventricular outflow tract velocity time integral (LVOT-VTI) are associated with 24-h adverse outcomes and fluid-responsiveness in Emergency Department (ED) suspected sepsis patients prior to substantial fluid administration. METHODS: A single-center, prospective cohort study of adult ED patients with suspected sepsis recruited between 5/2020 and 12/2023 (exclusions: receipt of >500 mL fluid, intubated, on vasopressors, or existing do not resuscitate/intubate). The primary outcome was a 24-h ordinal measure of mortality, intensive care unit (ICU) admission, or rapid response team (RRT) activation; and the secondary outcome was fluid-responsiveness (increase in LVOT-VTI ≥10% after a 500 mL fluid bolus). Multivariable ordinal and multinomial regression models were used. RESULTS: 545 patients had VExUS and 493 had LVOT-VTI measurements. 24.7% of VExUS 0 versus 56.5% of VExUS 3 patients died/admitted to ICU within 24 h. VExUS scores ≥1 were associated with increased mortality or ICU admission: VExUS 1: OR 2.37 (95%CI: 1.29-4.36); VExUS 2: OR 2.84 (95%CI: 1.64-4.92); VExUS 3: OR 4.09 (95%CI: 2.24-7.45). VTI alone was not associated with increased adverse outcomes. 23.5% of VExUS 0/VTI ≥ 17 cm patients died/admitted to ICU within 24 h versus 57.3% of VExUS 2-3/VTI < 17 cm (OR 3.67 [95%CI: 2.04-6.61]). 63.7% of VExUS 0 versus 21.1% of VExUS 3 were fluid-responsive. VExUS score ≥1 were associated with decreased odds of fluid-responsiveness: VExUS 1: OR 0.35 (95%CI: 0.19-0.63); VExUS 2: OR 0.20 (95%CI: 0.11-0.37); VExUS 3 OR 0.16 (95%CI: 0.07-0.36). 62.1% of LVOT-VTIs 17-20 cm were fluid-responsiveness (OR 2.01; 95%CI: 1.20-3.37) versus 47.3% in the VTI > 20 cm reference group and 45.8% in the VTI < 17 cm group. 62.1% of VExUS 0/VTI ≥ 17 cm patients were fluid-responsive (reference) versus 16.7% of VExUS 2-3/VTI < 17 cm (OR 0.16; 95% CI 0.07-0.34). CONCLUSION: In non-ventilated ED patients with suspected sepsis, VExUS scores ≥1 were associated with increased odds of 24-h mortality/ICU admission and RRT activation and decreased odds of fluid-responsiveness. Combining VExUS and LVOT-VTI assessments early in sepsis may improve prediction of adverse outcomes and better characterize fluid tolerance/responsiveness to guide individualized resuscitation, but further research is needed.