The Association Between the Duration of Acute Kidney Injury and New-onset Chronic Kidney Disease After Cardiac or Thoracic Aortic Surgery

Study Overview
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Brief Summary
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The investigators aimed to evaluate the association between the duration and stage of acute kidney injury (AKI) and the development of chronic kidney disease during postoperative three years in patients undergoing cardiac or thoracic aortic surgery.

Detailed Description
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Postoperative acute kidney injury (AKI) has been investigated as an important contributor to postoperative morbidity and mortality after cardiovascular surgery. Also, temporary worsening of renal function after aortic surgery is associated with higher long-term mortality. Although the associations between AKI and chronic kidney disease (CKD) in medical or other surgical settings were reported, only a few studies evaluated this relationship in patients undergoing cardiac surgery. More specifically, the association of the severity or duration of AKI with the risk of the development of new-onset CKD after cardiac surgery has not been clearly elucidated. It would be important to find predictors of the long-term renal function or risk factors for the development of CKD after cardiac surgery because postoperative management of high-risk patients to develop long-term renal dysfunction may prevent further deterioration in renal function and improve patient prognosis. The investigators aimed to evaluate (1) the long-term renal function after cardiac surgery and (2) the association between the duration and stage of acute kidney injury (AKI) and the development of chronic kidney disease during postoperative three years in patients undergoing cardiac or thoracic aortic surgery.

Official Title
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The Association Between the Duration of Acute Kidney Injury and New-onset Chronic Kidney Disease After Cardiac or Thoracic Aortic Surgery: a Retrospective Observational Cohort Study

Conditions
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Acute Kidney Injury, Chronic Kidney Disease, Stage 3, Chronic Kidney Disease, Stage 5, Cardiac Surgery, Thoracic Aortic Surgery

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients who underwent cardiac or thoracic aortic surgery under cardiopulmonary bypass at Seoul National University Hospital between 2008 and 2017 Exclusion Criteria: Those with off-pump coronary artery bypass Missing baseline serum creatinine Missing postoperative serum creatinine values of more than three among seven postoperative days Preoperative baseline chronic kidney disease with estimated glomerular filtration rate <60 ml/min/1.73m2

Ages Eligible for Study
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Minimum Age: 20 Years

Sexes Eligible for Study
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All

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 |
| --- | --- | --- |
| new-onset chronic kidney disease stage 3 or higher or mortality | development of new-onset chronic kidney disease stage 3 or higher or all-cause mortality developed during 3 years after surgery. The new-onset chronic kidney disease was defined by at least two estimated Glomerular Filtration Rate values <60 ml/min/1.73 m2 separated by an interval of at least three months. | during 3 years after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| new-onset chronic kidney disease stage 3 or higher or mortality | development of new-onset chronic kidney disease stage 3 or higher or all-cause mortality developed during 1 year after surgery | during 1 year after surgery | 
| new-onset chronic kidney disease stage 3 or higher or mortality | development of new-onset chronic kidney disease stage 3 or higher or all-cause mortality developed during 2 years after surgery | during 2 years after surgery | 
| Length of postoperative hospital stay | Length of postoperative hospital stay | during one month after surgery | 
| Length of postoperative intensive care unit stay | Length of postoperative intensive care unit stay | during one month after surgery | 
| intra-aortic balloon pulsation insertion | intra-aortic balloon pulsation insertion | during surgery and postoperative one week | 
| Reopen for surgical bleeding | Reopen for surgical bleeding | during one month after surgery | 
| Respiratory complication | a composite outcome including postoperative atelectasis, pneumonia, pulmonary edema, pleural effusion and pneumothorax | during one month after surgery | 
| in-hospital mortality | all-cause mortality during hospital stay | during one month after surgery | 
| Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | at three months after surgery | 
| Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | at one year after surgery | 
| Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | at two years after surgery | 
| Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | Incidence of estimated Glomerular Filtration Rate <60 mL/min/1.73m2 | at three years after surgery | 
| Dependence on the regular hemodialysis | Dependence on the regular hemodialysis | at three years after surgery | 
| estimated Glomerular Filtration Rate | estimated Glomerular Filtration Rate | at three months after surgery | 
| estimated Glomerular Filtration Rate | estimated Glomerular Filtration Rate | at one year after surgery | 
| estimated Glomerular Filtration Rate | estimated Glomerular Filtration Rate | at two years after surgery | 
| estimated Glomerular Filtration Rate | estimated Glomerular Filtration Rate | at three years after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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acute kidney injury, chronic kidney disease, cardiac surgery, thoracic aortic surgery