Renal Venous Flow and Cardiac Surgery-associated Acute Kidney Injury

Study Overview
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Brief Summary
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The prospective single-center study investigates the association between changes in Doppler-derived renal venous flow and cardiac surgery-associated acute kidney injury (CSA-AKI).

Detailed Description
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CSA-AKI is a common postoperative complication in patients undergoing open heart surgery, and is associated with increased mortality and morbidity. Venous congestion has been identified as the principal cause of cardiorenal decompensation in patients with heart failure but the relative contribution of congestion-driven renal function decline in CSA-AKI is not well studied. The prospective single-center study investigates whether serial Doppler-derived renal venous flow assessments could help identify subset of patients with cardiorenal syndrome and subclinical renal congestion at high risk of CSA-AKI.

Official Title
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Changes in Doppler-derived Renal Venous Flow and Adverse Renal Outcomes Following Cardiac Surgery

Conditions
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Acute Kidney Injury, Cardiorenal Syndrome

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Inclusion criteria: Subjects older than 18 years Subjects undergoing elective cardiac surgery (with or without cardiopulmonary bypass) Subjects who signed informed consent forms Exclusion Criteria: Patients requiring mechanical ventilation Patients with mechanical circulatory assist devices or extracorporeal membrane oxygenation Patients with stage 3 AKI with renal replacement therapy (RRT) or life- threatening volume overload treated with RRT Stage ≥4 chronic kidney disease (CKD) stage CKD requiring extracorporeal or peritoneal ultrafiltration for diuretic-resistant volume overload, 6) 6) Prediagnosed glomerulonephritis Autosomal dominant polycystic kidney disease, postrenal obstruction, or solid organ transplantation Anticipated life expectancy of <12 months Likelihood of receiving advanced therapy (mechanical circulatory assist device/cardiac transplant) Pregnancy or possibility of pregnancy in the next 3 months Rhabdomyolysis

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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: No intervention|No intervention|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association between perioperative changes in Doppler-derived renal venous venous flow and CSA-AKI | Doppler-derived renal venous flow | preoperative, 24 hours postoperative, hospital discharge | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association of changes in postoperative renal venous flow profiles with renal recovery at hospital discharge | Doppler-derived renal venous flow | Measured at Day 1 and Day 7 postoperative | 
| Estimated GFR trajectory up to 3 months post-cardiac surgery relative to kidney | Estimated GFR | Measured at 3 months post-surgery |