Acute Kidney InjuryNCT07821983
Renal Doppler Indices for Predicting Acute Kidney Injury After Isolated CABG
An observational study of Acute Kidney Injury and Coronary Artery Disease, run by Bursa Yuksek Ihtisas Training and Research Hospital at 1 site in Turkey (Türkiye).
Trial summary
Acute kidney injury can occur after coronary artery bypass grafting (CABG). This prospective, single-center observational study will evaluate whether two measurements obtained from renal Doppler ultrasound-the renal augmented velocity index (AVI) and renal resistive index (RRI)-can help predict postoperative acute… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Acute Kidney Injury, Coronary Artery Disease
- What is being tested?
- Renal Doppler Ultrasonography
- How many people
- 200 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 15 Sep 2026to Sep 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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: Adults scheduled for elective isolated on-pump coronary artery bypass grafting at Bursa Yuksek Ihtisas Training and Research Hospital who meet all eligibility criteria. Consecutive eligible patients will be approached before surgery.
Who may be able to join
- Age 18 years or older.
- Scheduled for elective isolated coronary artery bypass grafting with cardiopulmonary bypass (on-pump).
- Able and willing to provide written informed consent.
- Both kidneys present.
- Adequate bilateral preoperative renal Doppler signal for study measurements.
Who cannot join
- Preoperative chronic dialysis or renal replacement therapy.
- Urgent or emergency surgery.
- Combined cardiac surgery, including valve, aortic, or another major additional procedure.
- Off-pump coronary artery bypass grafting or conversion of the planned surgical technique.
- Clinically significant rhythm disturbance preventing acquisition of three interpretable cardiac cycles.
- Renal transplant, solitary kidney, significant renal artery stenosis, previous renal artery intervention, hydronephrosis, or other relevant renal vascular or structural disease.
- Inadequate bilateral preoperative renal Doppler examination.
- Withdrawal of consent.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site
Bursa Yuksek Ihtisas Training and Research Hospital
Bursa, Bursa
Nuri Burkay Soylu, MD, +90 538 248 4728, drburkaysoylu@gmail.com
Nuri Burkay Soylu, MD
About this study
Official title: Role of Renal Augmented Velocity Index and Resistive Index in Predicting Postoperative Acute Kidney Injury After Isolated Coronary Artery Bypass Grafting
Acute kidney injury can occur after coronary artery bypass grafting (CABG). This prospective, single-center observational study will evaluate whether two measurements obtained from renal Doppler ultrasound-the renal augmented velocity index (AVI) and renal resistive index (RRI)-can help predict postoperative acute kidney injury. About 200 adults undergoing elective isolated CABG with cardiopulmonary bypass will have bilateral renal Doppler examinations one day before surgery, within 60 minutes after admission to the intensive care unit, and 6 hours after intensive care unit admission. The primary outcome is acute kidney injury within the first 7 days after surgery, defined according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Ultrasound measurements will be analyzed offline and will not influence clinical care.
Read the detailed description
This is an academic, prospective observational cohort study at Bursa Yuksek Ihtisas Training and Research Hospital. Adults scheduled for elective isolated on-pump CABG who provide informed consent will be enrolled consecutively.
Bilateral renal Doppler waveforms will be obtained at three time points: T0, one day before surgery after at least 10 minutes of rest; T1, within the first 60 minutes after postoperative intensive care unit admission; and T2, 6 hours after intensive care unit admission. AVI and RRI will be calculated from stored waveforms by investigators blinded to clinical outcomes. No treatment decisions will be based on these study measurements. No additional blood or urine samples will be collected for research, and no biospecimens will be retained.
The primary analysis will assess the association and predictive performance of perioperative AVI and RRI measurements for KDIGO-defined acute kidney injury within 7 postoperative days. Secondary analyses will evaluate severe acute kidney injury, renal replacement therapy, mechanical ventilation duration, intensive care unit and hospital length of stay, major postoperative complications, 30-day mortality, renal function and renal recovery at day 30, and perioperative changes in AVI and RRI.
- Conditions
- Acute Kidney Injury, Coronary Artery Disease
- Being tested
- Renal Doppler Ultrasonography
- Keywords
- renal augmented velocity index, renal resistive index, renal Doppler ultrasonography, acute kidney injury, coronary artery bypass grafting, cardiac surgery, KDIGO, prognostic biomarker
- Medical subject headings
- Acute Kidney Injury, Coronary Artery Disease
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Renal Doppler UltrasonographyDiagnostic test
Also called Renal Doppler Ultrasound
Bilateral renal Doppler examinations are performed at T0 (one day before surgery after at least 10 minutes of rest), T1 (within the first 60 minutes after postoperative ICU admission), and T2 (6 hours after ICU admission). Renal augmented velocity index and renal resistive index are calculated offline from stored waveforms. Study measurements do not guide clinical care.
| Study group | Role | What they receive |
|---|---|---|
| Elective Isolated On-Pump CABG Cohort | Adults scheduled for elective isolated coronary artery bypass grafting with cardiopulmonary bypass. Bilateral renal Doppler ultrasonography is performed one day before surgery and at 0 and 6 hours after ICU admission. Renal augmented velocity index and renal resistive index measurements are analyzed offline and are not used to guide clinical care. Receives: Diagnostic Test: Renal Doppler Ultrasonography |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Acute Kidney Injury According to KDIGO Criteria
Number and percentage of participants who develop acute kidney injury according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria, based on serum creatinine and/or urine output.
Measured: From surgery through postoperative day 7
Secondary outcomes (9)
Incidence of KDIGO Stage 2 or 3 Acute Kidney Injury
Number and percentage of participants who develop KDIGO stage 2 or 3 acute kidney injury based on serum creatinine and/or urine output criteria.
Measured: From surgery through postoperative day 7
Need for Renal Replacement Therapy
Number and percentage of participants who require postoperative renal replacement therapy.
Measured: During the index hospitalization, up to 30 days after surgery
Duration of Mechanical Ventilation
Duration of invasive mechanical ventilation, measured in hours from postoperative intensive care unit admission until successful extubation.
Measured: During the index hospitalization, up to 30 days after surgery
Intensive Care Unit Length of Stay
Duration of postoperative intensive care unit stay, measured in days from intensive care unit admission to intensive care unit discharge.
Measured: During the index hospitalization, up to 30 days after surgery
Hospital Length of Stay
Duration of the index hospital stay, measured in days from surgery to hospital discharge.
Measured: During the index hospitalization, up to 30 days after surgery
Incidence of Major Postoperative Complications
Number and percentage of participants with one or more major postoperative complications, including low cardiac output syndrome, perioperative myocardial infarction, new atrial fibrillation or serious arrhythmia, stroke or transient ischemic attack, reoperation for bleeding, sepsis or serious infection, prolonged vasopressor requirement, or mechanical circulatory support.
Measured: During the index hospitalization, up to 30 days after surgery
All-Cause Mortality
Number and percentage of participants who die from any cause within 30 days after surgery.
Measured: Through 30 days after surgery
Renal Function and Renal Recovery at Day 30
Serum creatinine and estimated glomerular filtration rate at day 30 will be compared with preoperative baseline values to assess renal recovery.
Measured: 30 days after surgery
Change in Renal Doppler Indices
Change in renal augmented velocity index and renal resistive index from the preoperative T0 measurement to T1 and T2 postoperative measurements.
Measured: From one day before surgery through 6 hours after intensive care unit admission
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Sep 2026
- Study start15 Sep 2026 (estimated)
- Primary completionSep 2027 (estimated)
- Study completionSep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Acute Kidney InjuryStudies of the same condition, open and under way.
- 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
- Prospective
- Enrolment
- 200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Bursa Yuksek Ihtisas Training and Research Hospital
- Sponsor type
- Other government
- Responsible party
- Principal investigator, Nuri Burkay Soylu, Bursa Yuksek Ihtisas Training and Research Hospital
- Investigators
- Nuri Burkay Soylu, MD, Principal investigator, Bursa Yuksek Ihtisas Training and Research Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07821983
- Sponsor's protocol ID
- 2024-TBEK 2026/09-20
- Status last verified
- Sep 2026
- First submitted
- 10 Sep 2026
- Last updated
- 16 Sep 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 outside the study team. Access will be limited to the investigators specified in the approved study protocol.
Study at a glance
From the registry record, last updated by the sponsor on 16 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Role of Renal Augmented Velocity Index and Resistive Index in Predicting Postoperative Acute Kidney Injury After Isolated Coronary Artery Bypass Grafting
- ClinicalTrials.gov ID
- NCT07821983
- Acronym / sponsor ID
- 2024-TBEK 2026/09-20
- Conditions
- Acute Kidney Injury, Coronary Artery Disease
- Keywords
- renal augmented velocity index, renal resistive index, renal Doppler ultrasonography, acute kidney injury, coronary artery bypass grafting, cardiac surgery, KDIGO, prognostic biomarker
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 200 participants (estimated)
- Lead sponsor
- Bursa Yuksek Ihtisas Training and Research HospitalOther government
- Study start
- 15 Sep 2026 (estimated)
- Primary completion
- Sep 2027 (estimated)
- Study completion
- Sep 2027 (estimated)
- First posted
- 16 Sep 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 can occur after coronary artery bypass grafting (CABG). This prospective, single-center observational study will evaluate whether two measurements obtained from renal Doppler ultrasound-the renal augmented velocity index (AVI) and renal resistive index (RRI)-can help predict postoperative acute kidney injury. About 200 adults undergoing elective isolated CABG with cardiopulmonary bypass will have bilateral renal Doppler examinations one day before surgery, within 60 minutes after admission to the intensive care unit, and 6 hours after intensive care unit admission. The primary outcome is acute kidney injury within the first 7 days after surgery, defined according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Ultrasound measurements will be analyzed offline and will not influence clinical care.
Detailed description
This is an academic, prospective observational cohort study at Bursa Yuksek Ihtisas Training and Research Hospital. Adults scheduled for elective isolated on-pump CABG who provide informed consent will be enrolled consecutively.
Bilateral renal Doppler waveforms will be obtained at three time points: T0, one day before surgery after at least 10 minutes of rest; T1, within the first 60 minutes after postoperative intensive care unit admission; and T2, 6 hours after intensive care unit admission. AVI and RRI will be calculated from stored waveforms by investigators blinded to clinical outcomes. No treatment decisions will be based on these study measurements. No additional blood or urine samples will be collected for research, and no biospecimens will be retained.
The primary analysis will assess the association and predictive performance of perioperative AVI and RRI measurements for KDIGO-defined acute kidney injury within 7 postoperative days. Secondary analyses will evaluate severe acute kidney injury, renal replacement therapy, mechanical ventilation duration, intensive care unit and hospital length of stay, major postoperative complications, 30-day mortality, renal function and renal recovery at day 30, and perioperative changes in AVI and RRI.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Elective Isolated On-Pump CABG Cohort | – | Diagnostic Test: Renal Doppler UltrasonographyAdults scheduled for elective isolated coronary artery bypass grafting with cardiopulmonary bypass. Bilateral renal Doppler ultrasonography is performed one day before surgery and at 0 and 6 hours after ICU admission. Renal augmented velocity index and renal resistive index measurements are analyzed offline and are not used to guide clinical care. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adults scheduled for elective isolated on-pump coronary artery bypass grafting at Bursa Yuksek Ihtisas Training and Research Hospital who meet all eligibility criteria. Consecutive eligible patients will be approached before surgery.
Key inclusion criteria (5 listed)
- Age 18 years or older.
- Scheduled for elective isolated coronary artery bypass grafting with cardiopulmonary bypass (on-pump).
- Able and willing to provide written informed consent.
- Both kidneys present.
- Adequate bilateral preoperative renal Doppler signal for study measurements.
Key exclusion criteria (8 listed)
- Preoperative chronic dialysis or renal replacement therapy.
- Urgent or emergency surgery.
- Combined cardiac surgery, including valve, aortic, or another major additional procedure.
- Off-pump coronary artery bypass grafting or conversion of the planned surgical technique.
- Clinically significant rhythm disturbance preventing acquisition of three interpretable cardiac cycles.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Renal Doppler UltrasonographyAlso: Renal Doppler UltrasoundBilateral renal Doppler examinations are performed at T0 (one day before surgery after at least 10 minutes of rest), T1 (within the first 60 minutes after postoperative ICU admission), and T2 (6 hours after ICU admission). Renal augmented velocity index and renal resistive index are calculated offline from stored waveforms. Study measurements do not guide clinical care. | Diagnostic test | Elective Isolated On-Pump CABG Cohort |
Primary outcome
Incidence of Acute Kidney Injury According to KDIGO Criteria
Time frame: From surgery through postoperative day 7
Number and percentage of participants who develop acute kidney injury according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria, based on serum creatinine and/or urine output.
9 secondary outcomes
Incidence of KDIGO Stage 2 or 3 Acute Kidney Injury
Time frame: From surgery through postoperative day 7
Need for Renal Replacement Therapy
Time frame: During the index hospitalization, up to 30 days after surgery
Duration of Mechanical Ventilation
Time frame: During the index hospitalization, up to 30 days after surgery
Intensive Care Unit Length of Stay
Time frame: During the index hospitalization, up to 30 days after surgery
Hospital Length of Stay
Time frame: During the index hospitalization, up to 30 days after surgery
Incidence of Major Postoperative Complications
Time frame: During the index hospitalization, up to 30 days after surgery
All-Cause Mortality
Time frame: Through 30 days after surgery
Renal Function and Renal Recovery at Day 30
Time frame: 30 days after surgery
Change in Renal Doppler Indices
Time frame: From one day before surgery through 6 hours after intensive care unit admission
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Sep 2026.
- Individual participant dataSharing planned: No. Individual participant data will not be shared outside the study team. Access will be limited to the investigators specified in the approved study protocol.
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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.
Nuri Burkay Soylu, MD principal investigator
Bursa Yuksek Ihtisas Training and Research Hospital
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 Coronary Artery Disease, run by Bursa Yuksek Ihtisas Training and Research Hospital 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 5 inclusion and 8 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: opening soon, as of the sponsor's last update on 16 Sep 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Nuri Burkay Soylu, MD (+90 538 248 4728, drburkaysoylu@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Acute Kidney Injury According to KDIGO Criteria (time frame: From surgery through postoperative day 7). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 16 Sep 2026.