Clinical Research Directory

Doppler Evaluation for Congestive Acute Kidney Injury in Critical Illness

This study will evaluate the use of the Venous Excess Ultrasound (VExUS) score to guide fluid management in critically ill ICU patients through a prospective, multi-aim design combining observational and randomized components. The study will be conducted in the medical intensive care unit (MICU), multidisciplinary critical care unit (MCCU), and cardiac care unit (CCU) at UAB.

Quantification of Systemic Congestion by Ultrasound As a Predictor of Weaning Failure From Mechanical Ventilation

Mechanical ventilation is an essential, life-saving therapy in the ICU, allowing critically ill patients to rest and recover. Transitioning patients back to spontaneous breathing-known as weaning-is clinically challenging. The first attempt, the Spontaneous Breathing Trial (SBT), fails in 10-30% of cases. Identifying the mechanisms behind failure is crucial, as unsuccessful weaning prolongs ICU stay and increases the risk of reintubation, which worsens prognosis. The SCOUT study aims to improve prediction and management of weaning failure. The main objective of the study is to evaluate whether a specific ultrasound-based method, the Venous Excess Ultrasound Score (VExUS), can predict failure of weaning from mechanical ventilation. A key pathophysiological factor is systemic venous congestion. When a patient initiates an SBT, the increased respiratory effort shifts venous return and may precipitate cardiovascular decompensation with pulmonary fluid accumulation, termed weaning-induced pulmonary edema (WIPO). Notably, this may occur even in patients without known cardiac disease. Detecting clinically relevant congestion before SBT is difficult. Fluid balance and body weight are imprecise, physical examination lacks sensitivity, and biomarkers such as NT-proBNP have limited predictive capacity. VExUS offers a promising, non-invasive approach by directly assessing venous flow patterns in major veins (inferior vena cava, hepatic, portal, and renal veins), providing an estimation of systemic venous pressure and congestion. The central hypothesis is that elevated VExUS grades prior to SBT will identify patients at high risk of failure, enabling proactive optimization and potentially improving outcomes. SCOUT is designed as a prospective, multicenter, observational study. Standard clinical management of mechanical ventilation and weaning remains unchanged. After informed consent, baseline data will be obtained immediately before SBT, including vital signs, ventilator parameters, blood sampling, and three non-invasive ultrasound assessments: cardiac, pulmonary, and VExUS. During the 30-120-minute SBT, the patient breathes with reduced ventilatory support while their clinical tolerance is evaluated. At the end of the SBT, selected measurements are repeated. Weaning failure is defined as: early termination of SBT due to intolerance, need for invasive or non-invasive ventilation within 48 h after extubation, or death within 48 h. Data are anonymized and stored securely (REDCap) in compliance with Spanish and EU data protection regulations. The study is low-risk and provides no direct individual benefit, but may benefit future ICU patients by improving weaning strategies and prognostication.

Fluid Balance Guided by Modified Venous Excess Ultrasonography Versus Standard Care in Patients With Acute Kidney Injury Receiving Continuous Renal Replacement Therapy

The goal of this randomised controlled trial is to compare the cumulative fluid balance over the first 72 h following inclusion guided by mVExUS versus standard of care in critically ill patients with acute kidney injury receiving CRKT . It will also compare the proportion of CRRT-related complications-including intradialytic hypotension and arrhythmias-between patients managed with mVExUS-guided fluid management and those receiving standard care. The main questions it aims to answer are: Does fluid removal rate guided by mVExUS will reduce cumulative fluid balance over the course of the first 72 h of CRRT in ICU patients compared to standard care Participants will: Get fluid assessment by mVExUS protocol or a strandard care every 8 hours for 72 hours

Effect of VExUS Ultrasound Protocol (Venous Excess Ultrasound) on Perioperative Fluid Management, on the Incidence of Postoperative Pulmonary Complications and Postoperative Acute Kidney Injury in Patients Undergoing Thoracic Surgery

This study aims to investigate the effect of a VExUS ultrasound guided protocol of perioperative fluid management within a goal-directed therapy framework, on postoperative respiratory complications, and the occurrence of acute kidney injury (AKI) in patients undergoing thoracic surgery.

Prognostic Power of the VEXUS Score in Septic Shock: Effectiveness in Mortality Prediction

This study aims to evaluate the prognostic power of the VEXUS Score in predicting mortality among patients with septic shock in intensive care units.