Accuracy of Pre-existing Risk Scoring Models for Predicting Acute Kidney Injury in Patients Who Underwent Aortic Surgery Using a Gray Zone Approach

Study Overview
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Brief Summary
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Acute kidney injury after cardiac surgery has been reported to increase morbidity and mortality. Several risk scoring models for prediction of aortic kidney injury after cardiac surgery have been developed. However, predictive accuracy of these models is stil unclear. The aim of this study is to evaluate the accuracy of four pre-existing prediction models using a gray zone approach in patients who underwent aortic surgery in our institution.

Detailed Description
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Acute kidney injury after cardiac surgery has been reported to increase morbidity and mortality. Several risk scoring models for prediction of aortic kidney injury after cardiac surgery have been developed. However, predictive accuracy of these models is stil unclear. The aim of this study is to evaluate the accuracy of four pre-existing prediction models (AKICS, Wijeysundera, Mehta, and Thakar model)using a gray zone approach in patients who underwent aortic surgery in our institution. Based on receiver operating characteristic (ROC) curve analysis, we will construct a gray zone using the cut-off values with a sensitivity of < 90%, and a specificity of < 90% (diagnostic tolerance of 10%).

Official Title
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Accuracy of Pre-existing Risk Scoring Models for Predicting Acute Kidney Injury in Patients Who Underwent Aortic Surgery Using a Gray Zone Approach

Conditions
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Aortic Surgery, Postoperative Acute Kidney Injury

Intervention / Treatment
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* Procedure: elective or emergency aortic surgery (including ascending, arch, descending thoracic aorta)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Those who underwent elective or emergency aortic surgery in Samsung Medical Center during between 2004 and 2010. Exclusion Criteria: missing laboratory data preoperative hemodialysis death during or within 48 hours after surgery
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 |
| --- | --- |
| Patients who underwent aortic surgery<br>Patients who underwent aortic surgery in Samsung Medical Center during the period between 2004 and 2010 | Procedure: elective or emergency aortic surgery (including ascending, arch, descending thoracic aorta)<br> <br> * Other names: graft interposition of thoracic aorta;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| presence of acute kidney injury | abrupt (within 48 hours) reduction in kidney function currently defined as absolute increase in serum creatinine of more than or equal to 0.3 mg/dl (≥ 26.4 μmol/l), a percentage increase in serum creatinine of more than or equal to 50% (1.5-fold from baseline), or a reduction in urine output (documented oliguria of less than 0.5 ml/kg per hour for more than six hours) | within 48 hour after aortic surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gray zone range of each risk scoring model | Thresholds with as a sensitivity of < 90% and a specificity of < 90%. | within 48 hours | 
| Number of patients in the gray zone | Number of patients in the gray zone in each risk scoring model | within 48 hours after aortic surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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aortic surgery, acute kidney injury, gray zone approach