Acute Kidney InjuryAKI-CPBNCT07343830
Prediction of Acute Kidney Injury After Cardiac Surgery With Cardiopulmonary Bypass
An observational study of Acute Kidney Injury and Cardiac Surgery, run by Ataturk University at 1 site in Turkey (Türkiye).
Trial summary
Acute kidney injury (AKI) is a common and serious complication following cardiac surgery performed under cardiopulmonary bypass and is associated with increased morbidity, mortality, and prolonged hospital stay. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Acute Kidney Injury, Cardiac Surgery, Cardiopulmonary Bypass Surgery
- How many people
- 455 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 30 Jan 2026to 2 Feb 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adult patients undergoing cardiac surgery with cardiopulmonary bypass at a single tertiary care center.
Who may be able to join
- Adults aged 18 years or older
- Patients who underwent cardiac surgery under cardiopulmonary bypass
- Coronary artery bypass grafting, valve surgery, or combined cardiac surgery
- Elective or emergency procedures
Who cannot join
- Preoperative end-stage renal disease requiring dialysis
- Preoperative serum creatinine level greater than 4.0 mg/dL
- Off-pump cardiac surgery
- Missing preoperative or postoperative serum creatinine data
Trial locations and contacts
1 site in 1 country.
About this study
Official title: The Role of Preoperative Inflammation Markers, Renal Function, and Perfusion Stress in Predicting Acute Kidney Injury After Cardiac Surgery Under Cardiopulmonary Bypass: A Retrospective Cohort Study
Acute kidney injury (AKI) is a common and serious complication following cardiac surgery performed under cardiopulmonary bypass and is associated with increased morbidity, mortality, and prolonged hospital stay. Despite advances in perioperative management, the ability to accurately predict postoperative AKI remains limited.
Recent evidence suggests that preoperative inflammatory markers derived from routine laboratory tests, as well as indicators of intraoperative perfusion stress, may play an important role in the development of AKI. However, data evaluating these factors together in patients undergoing cardiac surgery with cardiopulmonary bypass are limited.
This retrospective observational cohort study aims to investigate the association between preoperative renal function, inflammatory indices, and intraoperative perfusion-related parameters with the development of postoperative AKI. Acute kidney injury will be defined according to the KDIGO serum creatinine criteria within the first 72 hours after surgery. The findings of this study may help identify patients at increased risk for AKI and contribute to improved perioperative risk stratification in cardiac surgery.
Read the detailed description
Acute kidney injury (AKI) is a frequent complication after cardiac surgery performed under cardiopulmonary bypass (CPB) and represents a major determinant of short- and long-term adverse outcomes. The pathophysiology of postoperative AKI is multifactorial and involves hemodilution, non-pulsatile flow, ischemia-reperfusion injury, systemic inflammatory response, and alterations in renal perfusion during CPB. Despite similar surgical and anesthetic management, not all patients develop AKI, suggesting that preoperative patient-related factors and intraoperative perfusion stress play a critical role.
In recent years, easily accessible inflammatory indices derived from routine hematological and biochemical parameters, such as the neutrophil-to-lymphocyte ratio, systemic immune-inflammation index, and C-reactive protein to albumin ratio, have been proposed as potential predictors of postoperative complications, including AKI. In addition, intraoperative parameters reflecting perfusion stress, such as cardiopulmonary bypass duration, arterial lactate levels, and acid-base disturbances, may further contribute to renal injury. However, studies evaluating these factors together in the setting of cardiac surgery with CPB are limited.
This single-center, retrospective observational cohort study will include adult patients who underwent cardiac surgery under cardiopulmonary bypass. Demographic data, comorbidities, preoperative laboratory parameters, echocardiographic findings, and intraoperative CPB-related variables will be collected retrospectively from institutional medical records. Acute kidney injury will be defined and staged according to the KDIGO serum creatinine criteria within 48-72 hours after surgery. Urine output criteria will not be evaluated due to limitations inherent to retrospective data collection.
The primary objective of the study is to identify independent predictors of postoperative AKI by assessing the combined effects of preoperative renal function, inflammatory markers, and intraoperative perfusion stress parameters. Secondary objectives include evaluation of AKI severity and in-hospital mortality. Multivariable logistic regression and receiver operating characteristic analyses will be used to determine the predictive value of selected parameters.
By improving understanding of the factors associated with postoperative AKI, this study aims to support better perioperative risk stratification and inform future prospective investigations in patients undergoing cardiac surgery with cardiopulmonary bypass.
- Conditions
- Acute Kidney Injury, Cardiac Surgery, Cardiopulmonary Bypass Surgery, Cardiac Surgery Associated - Acute Kidney Injury
- Keywords
- Acute kidney injury, Cardiac surgery, Cardiopulmonary bypass, Inflammatory markers, Neutrophil to lymphocyte ratio, Systemic immune inflammation index, C-reactive protein albumin ratio, Renal perfusion, Perfusion stress, KDIGO
- Medical subject headings
- Acute Kidney Injury
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Postoperative AKI | Patients who developed acute kidney injury within 72 hours after cardiac surgery under cardiopulmonary bypass, defined according to the KDIGO serum creatinine criteria. | |
| No Postoperative AKI | Patients who did not develop acute kidney injury within 72 hours after cardiac surgery under cardiopulmonary bypass according to the KDIGO serum creatinine criteria. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Postoperative Acute Kidney Injury
Development of acute kidney injury within 72 hours after cardiac surgery performed under cardiopulmonary bypass. Acute kidney injury will be defined according to the KDIGO serum creatinine criteria, based on an increase in serum creatinine of ≥0.3 mg/dL within 48 hours or ≥1.5 times baseline within 7 days. Urine output criteria will not be evaluated due to the retrospective nature of the study.
Measured: Within 72 hours after cardiac surgery
Secondary outcomes (2)
Severity of postoperative AKI (KDIGO stage)
AKI severity will be classified as KDIGO Stage 1-3 based on the change between preoperative creatinine (measured within 48 hours preoperatively) and the highest postoperative serum creatinine within the first 72 hours
Measured: Within 72 hours after cardiac surgery (postoperative days 0-3); assessed using the highest serum creatinine value measured every 12 hours (6 measurements)
In-Hospital Mortality
All-cause mortality during the index hospitalization following cardiac surgery, determined from hospital records
Measured: From the date of cardiac surgery through hospital discharge (index hospitalization), assessed at hospital discharge (up to 90 days)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Jan 2026
- Study start30 Jan 2026
- Primary completion2 Feb 2026
- Study completion2 Feb 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (8)Papers the sponsor has linked to this study.
- Other trials for Acute Kidney InjuryStudies of the same condition, open and under way.
- More trials run by Ataturk UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Retrospective
- Enrolment
- 455 participants (actual)
Sponsor and investigators
- Lead sponsor
- Ataturk University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mehmet Akif Yilmaz, Ataturk University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07343830
- Sponsor's protocol ID
- AKI-CPB-RETRO-2025
- Other IDs
- 2026/1
- Acronym
- AKI-CPB
- Status last verified
- Feb 2026
- First submitted
- 6 Jan 2026
- Last updated
- 4 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared due to the retrospective nature of the study and institutional data protection and patient confidentiality regulations. Only de-identified aggregate data will be reported in publications.
Publications
Khwaja A. KDIGO clinical practice guidelines for acute kidney injury. Nephron Clin Pract. 2012;120(4):c179-84. doi: 10.1159/000339789. Epub 2012 Aug 7. No abstract available.
PubMed 22890468Lee JW, Sharma AR, Lee SS, Chun WJ, Kim HS. The C-reactive protein to albumin ratio predicts postoperative complication in patients who undergo gastrectomy for gastric cancer. Heliyon. 2020 Jun 15;6(6):e04220. doi: 10.1016/j.heliyon.2020.e04220. eCollection 2020 Jun.
PubMed 32577578Sun J, Qi Y, Wang W, Meng P, Han C, Chen B. Systemic Immune-Inflammation Index (SII) as a Predictor of Short-Term Mortality Risk in Sepsis-Associated Acute Kidney Injury: A Retrospective Cohort Study. Med Sci Monit. 2024 Jun 28;30:e943414. doi: 10.12659/MSM.943414.
PubMed 38937949Bi JB, Zhang J, Ren YF, Du ZQ, Wu Z, Lv Y, Wu RQ. Neutrophil-to-lymphocyte ratio predicts acute kidney injury occurrence after gastrointestinal and hepatobiliary surgery. World J Gastrointest Surg. 2020 Jul 27;12(7):326-335. doi: 10.4240/wjgs.v12.i7.326.
PubMed 32821341Huen SC, Parikh CR. Predicting acute kidney injury after cardiac surgery: a systematic review. Ann Thorac Surg. 2012 Jan;93(1):337-47. doi: 10.1016/j.athoracsur.2011.09.010.
PubMed 22186469Lannemyr L, Bragadottir G, Hjarpe A, Redfors B, Ricksten SE. Impact of Cardiopulmonary Bypass Flow on Renal Oxygenation in Patients Undergoing Cardiac Operations. Ann Thorac Surg. 2019 Feb;107(2):505-511. doi: 10.1016/j.athoracsur.2018.08.085. Epub 2018 Oct 23.
PubMed 30365961Lagny MG, Jouret F, Koch JN, Blaffart F, Donneau AF, Albert A, Roediger L, Krzesinski JM, Defraigne JO. Incidence and outcomes of acute kidney injury after cardiac surgery using either criteria of the RIFLE classification. BMC Nephrol. 2015 May 30;16:76. doi: 10.1186/s12882-015-0066-9.
PubMed 26025079Hobson CE, Yavas S, Segal MS, Schold JD, Tribble CG, Layon AJ, Bihorac A. Acute kidney injury is associated with increased long-term mortality after cardiothoracic surgery. Circulation. 2009 May 12;119(18):2444-53. doi: 10.1161/CIRCULATIONAHA.108.800011. Epub 2009 Apr 27.
PubMed 19398670
Study at a glance
From the registry record, last updated by the sponsor on 4 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Role of Preoperative Inflammation Markers, Renal Function, and Perfusion Stress in Predicting Acute Kidney Injury After Cardiac Surgery Under Cardiopulmonary Bypass: A Retrospective Cohort Study
- ClinicalTrials.gov ID
- NCT07343830
- Acronym / sponsor ID
- AKI-CPB / AKI-CPB-RETRO-2025
- Conditions
- Acute Kidney Injury, Cardiac Surgery, Cardiopulmonary Bypass Surgery, Cardiac Surgery Associated - Acute Kidney Injury
- Keywords
- Acute kidney injury, Cardiac surgery, Cardiopulmonary bypass, Inflammatory markers, Neutrophil to lymphocyte ratio, Systemic immune inflammation index, C-reactive protein albumin ratio, Renal perfusion
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 455 participants (actual)
- Lead sponsor
- Ataturk UniversityUniversity, hospital or other
- Study start
- 30 Jan 2026 (actual)
- Primary completion
- 2 Feb 2026 (actual)
- Study completion
- 2 Feb 2026 (actual)
- First posted
- 15 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Acute kidney injury (AKI) is a common and serious complication following cardiac surgery performed under cardiopulmonary bypass and is associated with increased morbidity, mortality, and prolonged hospital stay. Despite advances in perioperative management, the ability to accurately predict postoperative AKI remains limited.
Recent evidence suggests that preoperative inflammatory markers derived from routine laboratory tests, as well as indicators of intraoperative perfusion stress, may play an important role in the development of AKI. However, data evaluating these factors together in patients undergoing cardiac surgery with cardiopulmonary bypass are limited.
This retrospective observational cohort study aims to investigate the association between preoperative renal function, inflammatory indices, and intraoperative perfusion-related parameters with the development of postoperative AKI. Acute kidney injury will be defined according to the KDIGO serum creatinine criteria within the first 72 hours after surgery. The findings of this study may help identify patients at increased risk for AKI and contribute to improved perioperative risk stratification in cardiac surgery.
Detailed description
Acute kidney injury (AKI) is a frequent complication after cardiac surgery performed under cardiopulmonary bypass (CPB) and represents a major determinant of short- and long-term adverse outcomes. The pathophysiology of postoperative AKI is multifactorial and involves hemodilution, non-pulsatile flow, ischemia-reperfusion injury, systemic inflammatory response, and alterations in renal perfusion during CPB. Despite similar surgical and anesthetic management, not all patients develop AKI, suggesting that preoperative patient-related factors and intraoperative perfusion stress play a critical role.
In recent years, easily accessible inflammatory indices derived from routine hematological and biochemical parameters, such as the neutrophil-to-lymphocyte ratio, systemic immune-inflammation index, and C-reactive protein to albumin ratio, have been proposed as potential predictors of postoperative complications, including AKI. In addition, intraoperative parameters reflecting perfusion stress, such as cardiopulmonary bypass duration, arterial lactate levels, and acid-base disturbances, may further contribute to renal injury. However, studies evaluating these factors together in the setting of cardiac surgery with CPB are limited.
This single-center, retrospective observational cohort study will include adult patients who underwent cardiac surgery under cardiopulmonary bypass. Demographic data, comorbidities, preoperative laboratory parameters, echocardiographic findings, and intraoperative CPB-related variables will be collected retrospectively from institutional medical records. Acute kidney injury will be defined and staged according to the KDIGO serum creatinine criteria within 48-72 hours after surgery. Urine output criteria will not be evaluated due to limitations inherent to retrospective data collection.
The primary objective of the study is to identify independent predictors of postoperative AKI by assessing the combined effects of preoperative renal function, inflammatory markers, and intraoperative perfusion stress parameters. Secondary objectives include evaluation of AKI severity and in-hospital mortality. Multivariable logistic regression and receiver operating characteristic analyses will be used to determine the predictive value of selected parameters.
By improving understanding of the factors associated with postoperative AKI, this study aims to support better perioperative risk stratification and inform future prospective investigations in patients undergoing cardiac surgery with cardiopulmonary bypass.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Postoperative AKI | – | –Patients who developed acute kidney injury within 72 hours after cardiac surgery under cardiopulmonary bypass, defined according to the KDIGO serum creatinine criteria. |
| No Postoperative AKI | – | –Patients who did not develop acute kidney injury within 72 hours after cardiac surgery under cardiopulmonary bypass according to the KDIGO serum creatinine criteria. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult patients undergoing cardiac surgery with cardiopulmonary bypass at a single tertiary care center.
Key inclusion criteria (4 listed)
- Adults aged 18 years or older
- Patients who underwent cardiac surgery under cardiopulmonary bypass
- Coronary artery bypass grafting, valve surgery, or combined cardiac surgery
- Elective or emergency procedures
Key exclusion criteria (4 listed)
- Preoperative end-stage renal disease requiring dialysis
- Preoperative serum creatinine level greater than 4.0 mg/dL
- Off-pump cardiac surgery
- Missing preoperative or postoperative serum creatinine data
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Postoperative Acute Kidney Injury
Time frame: Within 72 hours after cardiac surgery
Development of acute kidney injury within 72 hours after cardiac surgery performed under cardiopulmonary bypass. Acute kidney injury will be defined according to the KDIGO serum creatinine criteria, based on an increase in serum creatinine of ≥0.3 mg/dL within 48 hours or ≥1.5 times baseline within 7 days. Urine output criteria will not be evaluated due to the retrospective nature of the study.
2 secondary outcomes
Severity of postoperative AKI (KDIGO stage)
Time frame: Within 72 hours after cardiac surgery (postoperative days 0-3); assessed using the highest serum creatinine value measured every 12 hours (6 measurements)
In-Hospital Mortality
Time frame: From the date of cardiac surgery through hospital discharge (index hospitalization), assessed at hospital discharge (up to 90 days)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Feb 2026.
- Background: PubMed 22890468Khwaja A. KDIGO clinical practice guidelines for acute kidney injury. Nephron Clin Pract. 2012;120(4):c179-84. doi: 10.1159/000339789. Epub 2012 Aug 7. No abstract available.
- Background: PubMed 32577578Lee JW, Sharma AR, Lee SS, Chun WJ, Kim HS. The C-reactive protein to albumin ratio predicts postoperative complication in patients who undergo gastrectomy for gastric cancer. Heliyon. 2020 Jun 15;6(6):e04220. doi: 10.1016/j.heliyon.2020.e04220. eCollection 2020 Jun.
- Background: PubMed 38937949Sun J, Qi Y, Wang W, Meng P, Han C, Chen B. Systemic Immune-Inflammation Index (SII) as a Predictor of Short-Term Mortality Risk in Sepsis-Associated Acute Kidney Injury: A Retrospective Cohort Study. Med Sci Monit. 2024 Jun 28;30:e943414. doi: 10.12659/MSM.943414.
- Background: PubMed 32821341Bi JB, Zhang J, Ren YF, Du ZQ, Wu Z, Lv Y, Wu RQ. Neutrophil-to-lymphocyte ratio predicts acute kidney injury occurrence after gastrointestinal and hepatobiliary surgery. World J Gastrointest Surg. 2020 Jul 27;12(7):326-335. doi: 10.4240/wjgs.v12.i7.326.
- Background: PubMed 22186469Huen SC, Parikh CR. Predicting acute kidney injury after cardiac surgery: a systematic review. Ann Thorac Surg. 2012 Jan;93(1):337-47. doi: 10.1016/j.athoracsur.2011.09.010.
- Background: PubMed 30365961Lannemyr L, Bragadottir G, Hjarpe A, Redfors B, Ricksten SE. Impact of Cardiopulmonary Bypass Flow on Renal Oxygenation in Patients Undergoing Cardiac Operations. Ann Thorac Surg. 2019 Feb;107(2):505-511. doi: 10.1016/j.athoracsur.2018.08.085. Epub 2018 Oct 23.
- Background: PubMed 26025079Lagny MG, Jouret F, Koch JN, Blaffart F, Donneau AF, Albert A, Roediger L, Krzesinski JM, Defraigne JO. Incidence and outcomes of acute kidney injury after cardiac surgery using either criteria of the RIFLE classification. BMC Nephrol. 2015 May 30;16:76. doi: 10.1186/s12882-015-0066-9.
- Background: PubMed 19398670Hobson CE, Yavas S, Segal MS, Schold JD, Tribble CG, Layon AJ, Bihorac A. Acute kidney injury is associated with increased long-term mortality after cardiothoracic surgery. Circulation. 2009 May 12;119(18):2444-53. doi: 10.1161/CIRCULATIONAHA.108.800011. Epub 2009 Apr 27.
- Individual participant dataSharing planned: No. Individual participant data will not be shared due to the retrospective nature of the study and institutional data protection and patient confidentiality regulations. Only de-identified aggregate data will be reported in publications.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Acute Kidney Injury and Cardiac Surgery, run by Ataturk University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 4 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Postoperative Acute Kidney Injury (time frame: Within 72 hours after cardiac surgery). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07343830, which also lists 8 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Feb 2026.