Modified Venous Excess Ultrasound (mVExUS) in the Prediction of Ventilator Weaning Failure: a Cohort Study

Background: Ventilator weaning failure is a significant challenge in critically ill patients, and venous congestion has emerged as a potentially modifiable factor influencing weaning outcomes. This study aimed to investigate the association between venous congestion identified by the modified venous excess ultrasound (mVExUS) score and ventilator weaning failure in critically ill patients. Methods: We prospectively enrolled patients aged 18 years or older who had received mechanical ventilation (MV) for at least 48 hours. A mVExUS score, excluding the intrarenal component, and a lung point of care ultrasound (POCUS) assessment were performed before a spontaneous breathing trial (SBT). The primary outcome was weaning failure, defined as a failed SBT or the need for MV (invasive or non-invasive) within 72 hours. Results: Among 111 patients, 57 (51.4%) experienced ventilator weaning failure. Ventilator weaning failure occurred in 63.9% of patients with mVExUS scores of 2–3, compared to 45.3% with scores of 0–1 (p = 0.067). In adjusted analyses, mVExUS scores of 2–3 were independently associated with weaning failure (OR 2.756, p = 0.03). A post-hoc analysis combining mVExUS and lung POCUS scores showed a weaning failure incidence of 76.5% in patients with mVExUS scores of 2–3 and lung POCUS scores ≥7, compared to 34.1% in patients with mVExUS scores of 0–1 and lung POCUS scores <7 (p = 0.002). Conclusion: mVExUS scores of 2–3 are significantly associated with a higher risk of weaning failure and post-extubation respiratory failure. Combining VExUS and lung POCUS scores may enhance the assessment of weaning readiness in critically ill patients.