Cardiopulmonary Bypass, Circulation Disorder, Extracorporeal Circulation; Complications, Hemolysis, Inflammatory Response, Renal Failure, Renal Plasma Flow, Effective
Conditions
Keywords
renal oxygenation, renal blood flow, cardiopulmonary bypass, tubular cell injury, N-acetyl-beta-D-glucosaminidase, nephrocheck, inflammation, hemolysis
Brief summary
During open cardiac surgery, cardiopulmonary bypass (CPB) is used to temporarily replace the function of the heart and lungs. Renal ischemia resulting in acute kidney injury is common after cardiac surgery. The renal oxygenation is impaired during CPB, but the oxygenation may be improved by increasing the CPB blood flow. In this randomized study, two CPB flow rates will be compared regarding renal outcome (biomarkers and renal oxygenation/renal blood flow), as well as markers of inflammation and hemolysis. Additionally, urine oxygen tension will be measured during CPB and the early intensive care phase and compared to renal oxygenation. Regional oxygen saturation assessed with near infrared spectroscopy from the brain and kidneys will be monitored during and after surgery.
Interventions
PROCEDUREHigh CPB flow
Target CPB flow 2.9 L/min/m2 throughout the CPB period
Sponsors
Sahlgrenska University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Intervention model description
To compare normal (2.4 L/min/m2) and high (2.9 L/min/m2) cardiopulmonary bypass flow during cardiac surgery
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Written, signed informed consent * Male and female subjects ≥18 years * Left ventricular ejection fraction ≥30 % * Estimated GFR ≥30 ml/min using the CKD-EPI equation (Levey 2009) * Scheduled open cardiac surgery with CPB * Planned normothermia during CPB * Expected CPB time \> 60 minutes
Exclusion criteria
* Emergency surgery * Cardiac transplantation * Advanced grown-up congenital heart disease corrections * Previous cerebral infarction, verified with computed tomography or magnetic resonance imaging * Body mass index \> 32 kg/m2 * Use of hypothermia \< 32 °C during CPB * Inability of the patient to give based opinion * In the investigator´s opinion, the patient has a condition that could be adversely affected by study participation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Renal oxygen delivery and blood flow | 6 hours | Renal oxygen delivery during and after cardiopulmonary bypass (CPB) |
| Biomarker u-NAG | 24 hours | Tubulus injury biomarker N-acetyl-ß-d-glucoseaminidase (NAG) will be analyzed in urine with a spectrophotometric method and corrected for urine creatinine. |
| Biomarkers Nephrocheck | 24 hours | Renal biomarker assay Nephrocheck (IGFBP-7 x TIMP-2) will be analyzed in urine |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Inflammation IL-6 | 24 hours | Differences in inflammatory marker IL-6 |
| Inflammation IL-8 | 24 hours | Differences in inflammatory marker IL-8 |
| Inflammation IL-10 | 24 hours | Differences in inflammatory markers IL-1, IL-6, IL-8, IL-10 and TNFa |
| Inflammation TNFa | 24 hours | Differences in inflammatory marker TNFa |
| Complement activation | 24 hours | Differences in complement activation |
| Erythropoetin | 24 hours | Differences in serum-erythropoietin |
| Neuroinflammation Tau | 4 days | Changes in Tau |
| Neuroinflammation NF | 4 days | Changes Neurofilament |
| Kidney function | 24 hours | Measured glomerular filtration rate (iohexol clearance) on postoperative day 1 |
| Renal function | 24 hours | Measured glomerular filtration rate by iohexole clearance on the first postoperative day |
| Hemolysis | 24 hours | Differences in markers of hemolysis (free plasma Hb, LD, haptoglobin) |
| Serum creatinine and acute kidney injury (AKI) | 48 hours | Changes in serum creatinine |
| Inflammation IL-1 | 24 hours | Differences in inflammatory marker IL-1 |
Other
| Measure | Time frame | Description |
|---|---|---|
| Urinary pO2 | 24 hours | Changes in urinary pO2 measured with laser doppler technique. Correlation with global renal oxygenation will be explored. |
Countries
Sweden
Outcome results
None listed