New Methods for Early Detection of Acute Kidney Injury After Heart Surgery

Study Overview
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Brief Summary
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The investigators intend to study 2 new methods for the early detection of Acute Kidney Injury (AKI) after cardiac surgery and compare and combine the predictive abilities of these methods with established renal injury markers and epidemiological models to detect (AKI).

Detailed Description
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Acute Kidney Injury is common after Cardiac surgery and occurs in up to 20% of patients (Ref Rydén). This study will evaluate two new methods for the early detection of acute kidney injury in 200 patients undergoing elective cardiac surgery at the Karolinska Hospital. These methods are: Ultrasound based measurement of the kidneys blood flow profile measured using renal resistive index (RRI). This will be measured prior and within 4 hours post surgery. Ref Herzberg, Le Dorze. Urine creatinine clearance will be measured in the first four hours after cardiac surgery. The investigators will also measure known renal injury markers in blood and urine samples post operatively. These include Neutrophil gelatinise-associated lipocalin (NGAL), tissue inhibitor of metalloproteinases (TIMP-2), Insulin-like growth factor-binding protein 7 (IGFBP7), Kidney Injury Molecule 1 (KIM-1), Nephroclear, Interleukin 18 (IL-18), Fatty acid-binding protein (L-FABP), Fibulin-1, cystatin C och albumin. The new methods of AKI detection will be used to build a statistical model to predict AKI after cardiac surgery. We will determine whether the addition of renal injury markers and epidemiological factors known to be associated with the development of AKI (variables such as age, known chronic renal dysfunction or heart failure) can improve precision in diagnosis. AKI will be defined by the Kidney Disease improving Global outcomes (KDIGO) criteria (Ref KDIGO KDIGO Clinical Practice Guideline for Acute Kidney Injury, Khwaja A).

Official Title
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New Methods for Early Detection of Acute Kidney Injury After Heart Surgery

Conditions
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Acute Kidney Injury

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years and older Undergoing elective cardiac surgery (Coronary artery bypass grafting, valve surgery, aortic surgery or a combination). Able to understand and give written consent to partake in the study Exclusion Criteria: Unable to give consent Previously received a renal transplant Renal failure requiring dialysis prior to surgery Persistent atrial fibrillation

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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Acute kidney injury, no acute kidney injury<br>Acute kidney injury after cardiac surgery will be defined by KDIGO criteria, Creatinine rise from baseline and or urine production. | |
| No Acute Kidney Injury<br>No Acute kidney Injury after Cardiac surgery, according to KDIGO AKI definition | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute Kidney Injury | Acute Kidney Injury defined by KDiGO criteria | 48 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 30 day Mortality | Death occurring up to 30 days after cardiac surgery | 30 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cardiac surgery, renal resistive index, creatinine clearance