Renal Resistive Index in Early Detection of Postoperative Acute Kidney Injury

January 23, 2025 updated by: Musa Harun UÇAR, Bursa Yüksek İhtisas Education and Research Hospital

Effectiveness of Doppler Renal Resistive Index in Early Detection of Postoperative Acute Kidney Injury in Prolonged Cardiopulmonary Bypass Cardiac Surgeries

The primary aim of our study was to investigate the role of renal doppler ultrasonography (USG) and preoperative/postoperative renal resistive index (RRI) in the early prediction of AKI. Our secondary aim is to evaluate perioperative parameters that may cause AKI, to determine the duration of intensive care unit (ICU)/hospitalization and 30-day mortality.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Detailed Description

Our prospective, observational, cross-sectional study included patients with elective cardiac surgery under general anesthesia with prolonged CRP (>70 min) and aortic cross-clamp (ACC) (>60 min), >18 years of age, without preoperative acute/chronic renal failure, and with preoperative/postoperative RRI measurements. Demographic data, comorbidities, medications, preoperative ejection fraction, admission hematocrit (HCT) and baseline serum creatinine (sCr), type of operation, and preoperative RRI were recorded. Intraoperative operation and CPB/ACC duration, blood product transfusion, urine output, amount of bleeding, fluid balance, use of vasopressor/inotropic agents and diuretics, and complications were recorded. RRI was measured by the same radiologist in the first postoperative hour. Urine output and fluid balance, vasopressor/inotropic agent requirement, diuretic use, sKr, HCT level and blood product transfusion were recorded for 3 days postoperatively. According to KDIGO guidelines, patients who did not develop CCI-AKI were divided into 2 groups as Group 1 (n:64) and patients who developed CCI-AKI were divided into Group 2 (n:26). In Group 2, renal failure stage, duration (acute/chronic) and RRT were recorded. ICU and hospital length of stay, postoperative complications and 30-day mortality were recorded.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
143

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Turkey
      • Bursa, Turkey, 16000
        • Bursa High Specialization Training and Research Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Probability Sample

Study Population

Patients undergoing open heart surgery with cardiopulmonary bypass under general anesthesia

Description

Inclusion Criteria:

  • Elective cardiac surgeries under general anesthesia with prolonged CPB (>70 min) and aortic cross clemp (>60 min) time
  • >18 years of age, without preoperative acute or chronic renal failure
  • with preoperative and postoperative RRI measurements

Exclusion Criteria:

  • Patients with known renal insufficiency,
  • Patients with acute renal failure in the last 3 months
  • Emergency surgeries,
  • Patients with arrhythmia end-stage renal disease and renal transplant
  • Patients Patients with short duration of CPB (<70 min) and ACK (<60 min)
  • Failed Doppler ultrasonography imaging

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Group 1: Patients without CCI-AKI
atients who did not develop CCI-AKI postoperatively (n=64). Observational data collected on demographics, RRI, intraoperative and postoperative factors.
Group 2: Patients with CCI-AKI
Patients who developed CCI-AKI postoperatively (n=26). Data includes renal failure staging, RRT requirements, complications, and outcomes.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Preoperative-postoperative percentage change of RRI (∆RRI) between two groups
Time Frame: Cases between September 2022 and January 2024
The study aims to evaluate percentage change RRI (∆RRI) between two groups. Statistical analyses will be performed to compare magnitude of change in ∆RRI, between the groups.
Cases between September 2022 and January 2024
Postoperative RRI ROC analysis
Time Frame: Cases between September 2022 and January 2024
The study aims to assess the utility of postoperative renal resistive index (RRI) in predicting the development of cardiac surgery-associated acute kidney injury (CSA-AKI). Receiver operating characteristic (ROC) analysis will be employed to determine the discriminatory power of postoperative RRI and identify an optimal cut-off value for predicting CSA-AKI. Sensitivity, specificity, and predictive probabilities associated with the cut-off value will be evaluated.
Cases between September 2022 and January 2024
Postoperative grouping of patients according to KDIGO criteria
Time Frame: Cases between September 2022 and January 2024
The study plans to include 90 patients, categorized into two groups based on the KDIGO criteria for acute kidney injury (AKI): patients who do not develop cardiac surgery-associated AKI (CSA-AKI) and patients who do develop CSA-AKI. To analyze differences between the groups, specific clinical and biochemical parameters will be assessed and reported as separate outcome measures. These parameters will include [specific measurements, e.g., serum creatinine levels (mg/dL), estimated glomerular filtration rate (eGFR, mL/min/1.73m²), and urine output (mL/kg/hour)]. Each parameter will be assessed using standard laboratory or clinical methods, with units of measurement specified for each outcome. If multiple measurements are aggregated to generate a single outcome (e.g., BMI calculated from weight and height), this will be clearly described in the analysis.
Cases between September 2022 and January 2024
Comparison of preoperative, postoperative renal resistive index [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
The study aims to evaluate preoperative and postoperative renal resistive index (RRI) values between two groups. The renal resistive index (RRI) is a measure of renal vascular resistance obtained via Doppler ultrasound. . RRI values of 0.7 or higher are associated with worse renal outcomes, as they indicate increased vascular resistance. Statistical analyses will be performed to compare preoperative and postoperative RRI values between the groups.
Cases between September 2022 and January 2024

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Hematocrit Change over Time [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
The study will assess changes in intraoperative hematocrit (Hct) values over time. Hct levels will be measured at predefined stages of the operation, including the warm-up period, and comparisons between the groups will be conducted to evaluate potential differences.
Cases between September 2022 and January 2024
Distribution of Intraoperative Urine Output (mL) [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
The study will evaluate intraoperative urine output (mL) between the groups. Urine output will be measured at three distinct time points: before cardiopulmonary bypass (CPB), during CPB, and after CPB.
Cases between September 2022 and January 2024
Distribution of Intraoperative Administered Fluids (mL) [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
The study will evaluate the volume of fluids administered intraoperatively in both groups. The total volume of fluids administered (mL) during the intraoperative period will be recorded and analyzed.
Cases between September 2022 and January 2024
Distribution of Intraoperative Fluid Balance (mL) Between Groups [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
Fluid balance will be assessed intraoperatively as the difference between the total volume of fluids administered and the total output (urine and other losses). This parameter will be reported in mL and analyzed to identify differences between the groups.
Cases between September 2022 and January 2024
Comparison of Urine Output in the First 3 Postoperative Days Between and Within Groups [mean ± SD]
Time Frame: Cases between September 2022 and January 2024
The study will evaluate postoperative urine output in both groups over the first three days following surgery. Urine output will be measured daily, and comparisons will be conducted to assess differences between the groups at each time point.
Cases between September 2022 and January 2024
Comparison of Fluid Balance in the First 3 Postoperative Days Between and Within Groups[mean ± SD]
Time Frame: Cases between September 2022 and January 2024
The study will analyze 24-hour fluid balance values for the first three postoperative days. Daily fluid balance values will be compared between the groups to identify potential differences at each time point.
Cases between September 2022 and January 2024
Intergroup and Intragroup Comparison of Postoperative First 3 Days sKr Values [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
The study will assess serum creatinine (sCr) levels over the first three postoperative days. Comparisons will be made between the groups to evaluate differences in sCr values at each time point.
Cases between September 2022 and January 2024
Comparison of Postoperative Duration of ICU Stay, Duration of Hospitalization Between Groups (day) [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
This outcome measure will evaluate and compare the postoperative duration of ICU stay and the total duration of hospitalization (in days) between the two groups. The duration of ICU stay will be recorded as the total number of days patients spend in the ICU after surgery, while the duration of hospitalization will include the total number of days from admission to discharge. Both outcomes will be reported as median values (with minimum and maximum ranges) for each group. Statistical analyses will be conducted to identify any significant differences between the groups.
Cases between September 2022 and January 2024
Comparison of duration of postoperative mechanical ventilation (hour) [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
The study will compare the duration of postoperative mechanical ventilation between the groups. This outcome measure will record the total time (in hours) that patients require mechanical ventilation following surgery. Data will be presented as the median value with a range (minimum to maximum) to account for variability. Statistical analyses will be conducted to identify any significant differences in mechanical ventilation duration between the groups.
Cases between September 2022 and January 2024
Comparison of Postoperative prolonged mechanical ventilation (>6 hours) Between Groups [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
This outcome measure evaluates the incidence of prolonged postoperative mechanical ventilation, defined as ventilation duration exceeding 6 hours, in each group. The data will be reported as the percentage of patients requiring prolonged mechanical ventilation, along with the median duration of ventilation and its range (min-max). Statistical comparisons will be conducted to determine significant differences between the groups.
Cases between September 2022 and January 2024
Comparison of Postoperative 1-month mortality rate Between Groups [median (min-max)]
Time Frame: Cases between September 2022 and January 2024
The study will compare the postoperative 1-month mortality rate between the groups. This outcome measure represents the proportion of patients who die within 30 days after surgery. The mortality rate will be reported as a percentage and summarized using median (min-max) values for each group. Statistical analyses will be conducted to evaluate differences in 1-month mortality rates between the groups.
Cases between September 2022 and January 2024
Postoperative Blood and Blood Products Transfusion, n (percent)
Time Frame: Cases between September 2022 and January 2024
The study will assess the number of erythrocyte suspension (ES) transfusions required in each group. Subgroup analysis will be conducted to evaluate the incidence of transfusion requirements between the groups.
Cases between September 2022 and January 2024
KDIGO Stages in Patients with Renal Failure, n (percent)
Time Frame: Cases between September 2022 and January 2024
The study will assess the incidence of acute kidney injury (AKI) based on the Kidney Disease: Improving Global Outcomes (KDIGO) classification. The KDIGO staging system categorizes AKI into three stages (Stage 1 to Stage 3) based on serum creatinine levels and urine output. Higher stages indicate worse outcomes, reflecting greater severity of renal dysfunction. The study will also evaluate the occurrence of renal failure, the need for renal replacement therapy (RRT), and the rate of permanent renal failure. The timing of AKI onset and the need for interventions such as continuous renal replacement therapy (CRRT) or hemodialysis during the postoperative period will be monitored.
Cases between September 2022 and January 2024

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Bursa Yüksek İhtisas Education and Research Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
September 1, 2022

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 15, 2024

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
January 20, 2024

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
December 27, 2024

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 19, 2025

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
March 25, 2025

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
March 25, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 23, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
January 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2011-KAEK-25 2022/08-16

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Renal Insufficiency, Acute

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings