Evaluation of the Association Between the VEXUS Score and Hemodynamic Status and the Occurrence of Acute Kidney Injury After Open-Heart Surgery

Evaluation of the Association Between the VEXUS Score and Hemodynamic Status and the Occurrence of Acute Kidney Injury After Open-Heart Surgery

Acute kidney injury is a common complication after cardiac surgery with cardiopulmonary bypass and is associated with prolonged intensive care unit stay, increased morbidity, and mortality. Fluid overload and venous congestion are increasingly recognized as important contributors to postoperative organ dysfunction. The VExUS score is a bedside ultrasound tool that assesses systemic venous congestion through evaluation of the inferior vena cava and Doppler flow patterns in the hepatic, portal, and intrarenal veins. Although previous studies have suggested an association between VExUS-assessed venous congestion, AKI, and adverse outcomes, evidence regarding its relationship with advanced hemodynamic parameters remains limited. This prospective observational study will enroll adult patients undergoing cardiac surgery with cardiopulmonary bypass. All patients will undergo postoperative VExUS assessment and will be followed for the development of AKI and other postoperative complications. A predefined subgroup of patients undergoing clinically indicated PiCCO monitoring will additionally be evaluated to determine the association between VExUS score and PiCCO-derived hemodynamic parameters. The findings may support the use of VExUS as a noninvasive bedside tool for assessing venous congestion and identifying patients at increased risk of postoperative organ dysfunction after cardiac surgery.

Acute kidney injury remains a common complication after cardiac surgery with cardiopulmonary bypass and is associated with increased morbidity, mortality, and healthcare utilization. In addition to impaired cardiac output, growing evidence suggests that venous congestion plays an important role in the development of postoperative organ dysfunction. The VExUS score is an ultrasound-based tool that evaluates systemic venous congestion through assessment of the inferior vena cava and Doppler flow patterns in the hepatic, portal, and intrarenal veins. Previous studies have reported associations between venous congestion and adverse renal outcomes; however, data on the relationship between VExUS findings and advanced hemodynamic status in cardiac surgical patients remain limited.

This prospective observational study will be conducted in adult patients undergoing cardiac surgery with cardiopulmonary bypass. Postoperative VExUS assessments will be performed at predefined time points to evaluate the degree of venous congestion and its association with clinically relevant outcomes. All enrolled patients will be included in analyses examining the prognostic value of VExUS for postoperative AKI and other complications. In addition, a predefined subgroup of patients undergoing PiCCO monitoring as part of routine clinical care will be evaluated to investigate the relationship between VExUS scores and PiCCO-derived hemodynamic parameters.

The study aims to improve understanding of the role of venous congestion in postoperative organ dysfunction and to determine whether VExUS can serve as a practical noninvasive bedside tool for hemodynamic assessment and risk stratification following cardiac surgery.

Inclusion Criteria:

• Adult patients aged 18 years or older
• Undergoing elective or emergent open-heart surgery with the use of Cardiopulmonary Bypass (CPB)

Exclusion Criteria:

• Severe tricuspid regurgitation End-stage chronic kidney disease (estimated glomerular filtration rate below 15 mL per minute per 1.73 square meters)
• Preoperative use of an intra-aortic balloon pump (IABP)
• Preoperative use of extracorporeal membrane oxygenation (ECMO) or a ventricular assist device (VAD)
• Liver cirrhosis, portal hypertension, or portal vein thrombosis
• Refusal to participate by the patient or the patient's legally authorized representative