Supplementary Material for: Intra-dialytic Hypotension and the VExUS Assessment in Hospitalized Patients: A Prospective Cohort Study

Introduction: Predicting tolerance to fluid removal is particularly challenging in hospitalized, acutely ill patients. This study evaluated the association between the Venous Excess Ultrasound (VExUS) and IDHE in hospitalized patients.

Methods: This single-center prospective cohort included hospitalized between 2022 and 2024 receiving hemodialysis. Ultrasound of the inferior vena cava (IVC), hepatic, portal, and femoral veins was performed. Patients were classified into four VExUS grades (0 to 3) based on IVC dimensions and venous Doppler waveforms. Follow-up at 3 months was conducted to evaluate outcomes across the different groups.

Results: The cohort consisted of 93 patients for whom underwent ultrasound assessment. VExUS grading showed grade 0 in 52 patients (55.9%), grade 1 in 22 patients (23.7%), grade 2 in 11 patients (11.8%), and grade 3 in 8 patients (8.6%). The incidence of IDHE was tended to be higher in VExUS grade 0 (40.4%) and VExUS grade 3 (50.0%) patients compared with VExUS grade 1 (18.2%) or 2 (18.2%) (p=0.145). The cumulative duration of hypotension (sBP < 90 mmHg) differed between VExUS groups (p=0.03), with VExUS grade 3 patients experiencing longer median duration of hypotension compared to participants with a VExUS grade 1 (16.4 [0; 47.5] vs 0 [0; 0] minutes, p=0.04).

Discussion: Our findings showed a trend toward more frequent IDHE in both VExUS grade 0 and grade 3, with grade 3 patients experiencing a significantly longer cumulative duration of hypotension. High VExUS scores may identify patients at increased risk of hypotension due to impaired hemodynamic adaptability.