Cardiac Surgery Subjects
Conditions
Keywords
renal oxygenation, urine oxygen tension, furosemide, balanced diuresis
Brief summary
The PuO2 in RenalGuard (PURE) study is planned as a single center, randomized controlled pilot study comparing renal oxygenation during cardiac surgery with cardiopulmonary bypass (CPB) with or without balanced forced diuresis using the RenalGuard (RG) system. Renal oxygenation will be assessed by urine oxygen tension, continuously measured by optodes placed through the urine catheter. Measurements will start after induction of anesthesia and continue for 24 hours. In total, 30 patients will be randomized 1:1 to RG or standard of care (SOC) during cardiac surgery with CPB. In the RG group, the forced diuresis with neutral fluid balance will be maintained from before the start of surgery until 3 hours after weaning from CPB. The primary endpoint is the group difference (RG vs SOC) in delta PuO2, defined as the change in mean PuO2 from baseline to the last 5-minute period at 45 minutes after start of CPB. The secondary endpoints include 1. Group difference in mean PuO2 before, during and after CPB 2. Group difference in time weighted area under the curve for PuO2 3. Group differences in renal near infrared spectroscopy (NIRS) before, during and after CPB 4. Group difference in urine and blood biochemistry including renal biomarkers 5. Group difference in urine output and fluid balance during surgery and first postoperative day 6. Group differences in postoperative AKI according to the KDIGO criteria 7. Time (minutes) with puO2 ≤ 15 and ≤ 10 mmHg during and after CPB 8. Dynamics of PuO2 during the early postoperative phase Patients ≥18 years scheduled for cardiac surgery with CPB with estimated glomerular filtration rate ≥50 ml/min are eligible for inclusion. Exclusion criteria include patients on higher doses of furosemide, patients with AKI or under renal replacement therapy. Patients will be analyzed according to study group. In patients where hemofiltration has been used during CPB, control group patients who has received furosemide and patients in the RG group who do not reach target urine flow will be excluded from the main analysis but will be included in a separate analysis.
Interventions
DEVICERenalGuard Therapy
Fluid management system, which weighs urine and controls intravenous administration of crystalloid solution.
Sponsors
Sahlgrenska University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Patients ≥18 years of age * scheduled for cardiac surgery with normothermic CPB * Estimated glomerular filtration rate ≥50 ml/min as assessed by the CKD-EPI formula
Exclusion criteria
* Patient receiving furosemide at a dose\>100 mg/day orally (or the equivalent dose of an alternative loop diuretic) in the last week * Patient who cannot be urethrally catheterized for any reason * Patient already dialysis dependent * Known or suspected AKI (KDIGO criteria) at the time of screening * Any condition which, in the judgement of the investigator, might increase the risk to the patient
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Delta PuO2 | Baseline (before start of surgery) to 45 minutes after start of CPB | The primary endpoint is the group difference (RG vs controls) in delta PuO2, defined as the change in mean PuO2 from baseline to the last 5-minute period at 45 minutes after start of cardiopulmonary bypass (CPB) (or the last 5 minutes if cross clamp release is done before) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Repeated PuO2 | baseline, 30, 45 minutes on CPB and at 30, 60 and 240 minutes after CPB | Group difference in mean PuO2 at specified times |
| PuO2 AUC | From baseline before start of surgery until 4 hours after CPB | Group difference in time weighted area under the curve (AUC) for PuO2 during CPB and until removal of the PuO2 measurement |
| PuO2 sub threshold | From baseline before surgery until 4 hours after CPB | Time (minutes) with puO2 ≤ 15 and ≤ 10 mmHg during and after CPB |
| Diuresis and fluid balance | 24 hours | Diuresis and net fluid balance (incorporating fluids given and lost) during surgery and during the first 24 hours. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Urine Nephrocheck | 4 hours after CPB | Urine IGFBP2\*TIMP2 at 4 hours after Cardiac surgery |
| Renal near-infrared spectroscopy (NIRS) | From baseline before surgery until 4 hours after CPB | Group differences in renal NIRS at baseline, 30 minutes on CPB and at 30, 60 and 240 minutes after CPB |
| Creatinine | 7 days | Development of serum creatinine from baseline and daily for up to seven postoperative days |
| Dynamics of PuO2 during the early postoperative phase | 24 hours | Repeated measurements of PuO2 during the first postoperative 24 hours. |
Contacts
Primary ContactLukas Lannemyr Lannemyr, MD, PhD
Outcome results
None listed