External Validation of the VExUS Score for the Prediction of Acute Renal Failure in Cardiac Surgery

Study Overview
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Brief Summary
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Acute renal failure is a frequent complication associated with significant morbidity and mortality in postoperative cardiac surgery. The VExUS (Venous Excess UltraSound grading system) score was created to qualitatively assess this venous congestion, based on ultrasound data from patients obtained post operatively in cardiac surgery. These data included: inferior vena cava diameter, Doppler flow of the suprahepatic veins, portal trunk and renal veins. This score is predictive of the onset of acute renal failure in the first 3 days after surgery. The VExUS score has not been validated in an external and prospective way in cardiac surgery.

Detailed Description
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Acute renal failure is a frequent complication associated with significant morbidity and mortality in postoperative cardiac surgery. The pathophysiology in this context is complex, poorly understood and the causes are multiple: underlying nephropathy, intra- or postoperative haemodynamic instability, the use of an extracorporeal circulation, inflammation, etc. One of the other possible etiologies is venous congestion. This may be due to volume overload and/or isolated global or right heart dysfunction. Early treatment could prevent the onset of ARF or reduce its consequences, hence the importance of being able to predict its onset. The VExUS (Venous Excess UltraSound grading system) score was created to qualitatively assess this venous congestion, based on ultrasound data from patients obtained post operatively in cardiac surgery. These data included: inferior vena cava diameter, Doppler flow of the suprahepatic veins, portal trunk and renal veins. This score is predictive of the onset of acute renal failure in the first 3 days after surgery. The VExUS score has not been validated in an external and prospective way in cardiac surgery.

Official Title
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External Validation of the VExUS Score for the Prediction of Acute Renal Failure in Cardiac Surgery

Conditions
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Renal Failure, Acute Renal Failure, Renal Insufficiency, Acute Renal Insufficiency

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Scheduled cardiac surgery Affiliated to a social security system Exclusion Criteria: Emergency surgery Chronic renal failure defined by a glomerular filtration rate of less than 30ml/min or dialysis. renal transplant recipients Cirrhosis and portal hypertension Setting up a left ventricular assist device implantation Patient under ECMO (ExtraCorporeal Membrane Oxygenation), intra-aortic balloon pump, or a mechanical circulatory support device such as IMPELLA No available operator to perform ultrasound scans Patients objecting to the use of their data in research Subject under guardianship or subject deprived of freedom Pregnant or breastfeeding women Resume surgery within 48 hours of scheduled surgery Lack of a trained operator to perform D+1 and D+2 ultrasound

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association between the change in ultrasound data collected in the VExUS score and postoperative acute renal failure (defined by a creatininemia increase by 26.5 µmol/L in 48 hours). | correlation between operator in term of VExUS staging (VExUS score will be assessed at day 1, 2 and 3 after the surgery, in intensive care unit. | From date of randomization until date of post-operative acute renal failure (detected by daily creatininemia), assessed up to a variable period of time estimated to 2 weeks. | 
| Association between the change in ultrasound data collected in the VExUS score and postoperative acute renal failure. | Specificity of the VExUS score to predict an acute kidney failure will be evaluated | From date of randomization until date of post-operative acute renal failure (detected by daily creatininemia), assessed up to a variable period of time estimated to 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between the VExUS score and a postoperative acute renal failure | Use of a multivariable COX regression to evaluate the correlation between the VExUS score measured at day 1, 2 and 3 and a post-operative acute renal failure during the stay in intensive care unit | 3 days | 
| Diagnostic performances of the VExUS Score for postoperative acute renal failure | Sensitivity, NPV, PPV | 3 days | 
| Correlation between central venous pressure (CVP) and postoperative acute renal failure. If a statistical association is present, diagnostic performance (Sensitivity, Specificity, NPV, PPV) of the value | Central venous pressure (CVP). The values will be taken during the ultrasound scans at Day 0, Day 1 and Day 2. The units of pressure are mmHg. A value greater than 12mmHg will be considered high, a lower value as not high. The CVP is measured by a central venous line. | 3 days | 
| Correlation between daily fluid balance and postoperative acute renal failure. If a statistical association is present, diagnostic performance (Sensitivity, Specificity, NPV, PPV) of the value | Water balance: 24-hour input-output balance, in millilitres, collected daily. Values measured at Day 0, Day 1, Day 2 | 3 days | 
| Correlation between daily fluid balance and postoperative acute renal failure. If a statistical association is present, diagnostic performance (Sensitivity, Specificity, NPV, PPV) of the value | Water balance: including the weight in Kg compared to the reference weight established during the anaesthetic consultation. Values measured at Day 0, Day 1, Day 2 | 3 days | 
| Correlation between an isolated component of the VExUS score, echocardiography and postoperative acute renal failure. If a statistical association is present, diagnostic performance (Sensitivity, Specificity, NPV, PPV) of the value | An isolated component of the VExUS score that is measured at D0; D1; D2 by ultrasound Inferior vena cava diameter Doppler profile of the suprahepatic vein Doppler profile of portal vein Renal vein Doppler profile | 3 days | 
| Correlation between an echocardiographic abnormality and postoperative acute renal failure. If a statistical association is present, diagnostic performance (Sensitivity, Specificity, NPV, PPV) of the value. | Ultrasound assessment of the left and right heart: Visual LVEF, sub-aortic LTI, Mitral Doppler (E wave, A wave, E/A ratio, deceleration time), LV/VD ratio (less than or greater than 0.6); TAPSE (unit: mm); S wave (unit: cm/seconds); LTI flow (unit: m/seconds); diameter (unit: mm) and ICV compliance. Values also taken at D0, D1 and D2. | 3 days | 
| Correlation between VExUS score and the use of extra renal replacement therapy | Use of extra renal replacement therapy: based on dialysis prescriptions, binary value (yes/no) regardless of the method used (CVVHF, CVVHDF, CVVHD) | From randomization until date of postoperative need of extra renal replacement therapy, assessed up to a variable period of time estimated to 2 weeks. | 
| Correlation between VExUS score and length of stay | Length of stay in days: in intensive care, cardiac surgery and rehabilitation. Determined thanks to medical records. | From randomization until date of discharge, assessed up to a variable period of time estimated to 2 weeks. | 
| Correlation between VExUS score and 1-month mortality | Mortality: binary (yes/no) at 1 month. The data will be collected by phone call to the patient or a relative, or by consulting the medical record. | 1 month after admission in intensive care | 
| Correlation between renal arterial resistance index and postoperative acute renal failure. If a statistical association is present, diagnostic performance (Sensitivity, Specificity, NPV, PPV) | Renal arterial resistance index are measured at D0; D1; D2 during the ultrasound scans. | 3 days | 
| Correlation between renal venous impedance index and postoperative acute renal failure. If a statistical association is present, diagnostic performance (Sensitivity, Specificity, NPV, PPV) | Veinous impedance index are measured at D0; D1; D2 during the ultrasound scans. | 3 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Renal failure, Cardiac surgery, VExUS score, venous congestion