An observational study in Intraoperative, Venous Congestion and Cardiac Surgery-associated Acute Kidney Injury, sponsored by Zhuan Zhang. Completed at 1 site in China. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by Zhuan Zhang · Observational
Venous pressure is often overlooked as an important hemodynamic parameter. Elevated venous pressure and blood stasis in organ tissues can lead to interstitial edema. Intraoperative venous blood stasis can rapidly increase interstitial pressures within organ tissues, especially in organs encapsulated by tissue envelopes, such as the kidney, thereby rapidly reducing effective circulating blood flow to the organ. Systemic venous blood stasis, which tends to occur in patients with right heart failure or pulmonary hypertension, as well as in patients with fluid overload, can lead to intraoperative stasis in multiple organs and tissues, mediating the development of multisystem complications, including acute kidney injury. Therefore, timely, effective, and accurate intraoperative assessment of systemic venous blood stasis is particularly important.
When right heart failure and/or volume overload occurs in the body, changes in right atrial pressure are transmitted to the venous system of organs throughout the body, with dilatation of the inferior vena cava (IVC), obstruction of blood return from the hepatic, portal, and renal veins, and abnormal venous flow signals and altered ultrasound Doppler flow patterns.
The primary objective of this prospective cohort study is to explore if intraoperative systemic venous congestion during cardiac surgery is associated with postoperative CSA-AKI. In doing so, we seek to identify a promising physiological marker that can provide cues for the prediction of CSA-AKI. This study will also investigate the relationship between intraoperative systemic venous congestion and postoperative complications, and explore the relationship between each separate venous congestion and AKI after cardiac surgery.
98 studies on the registry are indexed under Hyperemia; 44 are open to participants now.
This study's enrollment of 135 is above the median of 100 across 46 observational studies indexed under Hyperemia.
Browse Hyperemia studies →Zhuan Zhang is the lead sponsor of 16 studies on the registry; 4 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients scheduled to undergo elective cardiac surgery
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adult patients scheduled to undergo elective cardiac surgery
Other: collection of demographic characteristics and comorbidities · Other: surgery-related parameters and kidney function assessments · Other: collection of biological (laboratory) parameters · Other: collection of hemodynamic parameters · Other: collection of echocardiographic parameters and venous ultrasound assessments
1. gender, age, BMI, ASA classification, NYHA (New York Heart Association) classification. 2. smoking history, medical history (hypertension, diabetes mellitus, Hyperlipidemia, stroke, anaemia, chronic obstructive pulmonary disease, pulmonary hypertension, preoperative atrial fibrillation, peripheral artery disease), preoperative ACEI, ARB, beta-blockers, loop diuretics, contrast agent, aspirin, and spironolactone use.
1. surgery type, surgery duration, CPB duration, aortic cross-clamp duration, blood loss, intraoperative fluid infusion, intraoperative urine output, intraoperative blood transfusion, intraoperative anesthetics and vasoactive medications. 2. baseline and postoperative eGFR, duration of mechanical ventilation, duration of vasopressor support, postoperative CRRT initiation, major bleeding, deep sternal wound infection/mediastinitis, surgical re-intervention, ICU LOS, hospital LOS, postoperative stroke, postoperative delirium, complications up to 30 days after surgery, 30-day inpatient mortality, survival status at discharge, and one year follow-up. 3. a composite endpoint of major complications after surgery defined as at least one of the following: death, prolonged ventilation (\>24 h), stroke, severe AKI, deep sternal wound infection, and reoperation for any reason. 4. CSA-AKI diagnosed using the KDIGO criteria. 5. acute kidney disease assessment. 6. major adverse kidney events.
1. WBC, CRP, IL-6, IL-1β, TNF-α, serum Amyloid A, procalcitonin, catecholamines, cortisol, SOD. 2. creatinine, uric acid, BUN, CysC, β2-MG, eGFR. 3. CK-MB, high-sensitivity troponin, NT pro-BNP, BNP. 4. hemoglobin, hematocrit, sodium, arterial lactate, liver enzymes.
1. blood pressure, heart rate, CVP; 2. CO, CI, SV, SVI,SVV; 3. intra-abdominal pressure; 4. vasoactive drug doses in the first hour in the ICU.
1. Left ventricle systolic function, including LVOT, LVEF, MPI; left ventricular diastolic function, including mitral flow-derived Doppler indices, pulmonary vein Doppler indices. 2. Right ventricular systolic function, including TAPSE. Right ventricular diastolic function, inferred from an hepatic vein flow in the absence of a dysrhythmia or pacing. 3. Inferior vena cava (IVC) measurements. 4. Hepatic vein Doppler parameters. 5. Portal vein Doppler parameters. 6. Renal vein Doppler parameters. 7. Renal artery blood flow Doppler parameters.
Acute kidney injury defined by an increase in serum creatinine of ≥150% of baseline or an elevation of 0.3 mg/dL or more within a contiguous period of 48 hours. (KDIGO criteria)
Time frame: 7 days after surgery
Plan to share: No
No publications or documents are linked to this record.
Ran from Oct 2024 to primary completion in Jul 2026, 21 months.
Of 28 observational studies under Hyperemia, half reached primary completion within 21 months of starting (the median), counting those still running; a quarter within 16 and three quarters within 27. This study's 21 months is close to that.
Since we started tracking on Sep 25, 2026, the dates moved once, on Nov 9, 2026: primary completion Sep 2026 → Jul 2026 and completion Sep 2026 → Jul 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Nov 2025. You cannot join it, but the record below documents what was studied.
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Zhuan Zhang