Cardiac Surgery SubjectsPURENCT06886191
PuO2 in RenalGuard Pilot Study
A study testing RenalGuard Therapy in people with Cardiac Surgery Subjects, run by Sahlgrenska University Hospital.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 85 years
- Conditions the study is for
- Cardiac Surgery Subjects
- What is being tested?
- RenalGuard Therapy
- Type of treatment
- Injection or infusion, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- No sites listed yet
- Study dates
- 17 Mar 2025to 31 Dec 2026
- Phase
- Interventional
- 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 to 85 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Who cannot join
- 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
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Effects on Urine Oxygenation of Forced Diuresis with Neutral Fluid Balance During Cardiac Surgery, a Randomized Controlled Trial
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.
Read more
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
- Group difference in mean PuO2 before, during and after CPB
- Group difference in time weighted area under the curve for PuO2
- Group differences in renal near infrared spectroscopy (NIRS) before, during and after CPB
- Group difference in urine and blood biochemistry including renal biomarkers
- Group difference in urine output and fluid balance during surgery and first postoperative day
- Group differences in postoperative AKI according to the KDIGO criteria
- Time (minutes) with puO2 ≤ 15 and ≤ 10 mmHg during and after CPB
- 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.
- Conditions
- Cardiac Surgery Subjects
- Being tested
- RenalGuard Therapy
- Keywords
- renal oxygenation, urine oxygen tension, furosemide, balanced diuresis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
RenalGuard TherapyDevice
Fluid management system, which weighs urine and controls intravenous administration of crystalloid solution.
| Study group | Role | What they receive |
|---|---|---|
| RenalGuard (RG) | Experimental | The RG system is used to ensure neutral (0) fluid balance while maintaining a urine flow >200 ml/hour. Urine output is replaced 1:1 with Plasmolyte solution. In patients randomized to RG, therapy is initiated after baseline measurements but before the start of surgery.
If baseline urine flow is < 200 ml/hour, a bolus dose of furosemide (20 mg iv) is given, and additional furosemide bolus and/or titration of continuous furosemide infusion may be given to maintain urine flow rate >200ml/hour.
After completed surgery, RG therapy continues until 3 hours after weaning from CPB Receives: Device: RenalGuard Therapy |
| Standard of Care | No intervention | Conduct of cardiopulmonary bypass will be done according to local clinical practice |
What is being measured
The primary outcome is the main question the study is designed to answer.
Delta PuO2
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)
Measured: Baseline (before start of surgery) to 45 minutes after start of CPB
Secondary outcomes (4)
Repeated PuO2
Group difference in mean PuO2 at specified times
Measured: baseline, 30, 45 minutes on CPB and at 30, 60 and 240 minutes after CPB
PuO2 AUC
Group difference in time weighted area under the curve (AUC) for PuO2 during CPB and until removal of the PuO2 measurement
Measured: From baseline before start of surgery until 4 hours after CPB
PuO2 sub threshold
Time (minutes) with puO2 ≤ 15 and ≤ 10 mmHg during and after CPB
Measured: From baseline before surgery until 4 hours after CPB
Diuresis and fluid balance
Diuresis and net fluid balance (incorporating fluids given and lost) during surgery and during the first 24 hours.
Measured: 24 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted20 Mar 2025
- Study start17 Mar 2025 (estimated)
- Primary completion31 Dec 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Cardiac Surgery SubjectsStudies 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Sahlgrenska University Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Lukas Lannemyr, Sahlgrenska University Hospital
- Investigators
- Lukas Lannemyr Lannemyr, MD, PhD, Principal investigator, Institute of Clinical Sciences, Dept of Anesthesia and Intensive Care, Sahlgrenska Academy, Gothenburg University. Gothenburg, Sweden
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06886191
- Sponsor's protocol ID
- PUREstudy
- Acronym
- PURE
- Status last verified
- Mar 2025
- First submitted
- 10 Mar 2025
- Last updated
- 20 Mar 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- Undecided: Parts of the data may be analyzed in other projects
Study at a glance
From the registry record, last updated by the sponsor on 20 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effects on Urine Oxygenation of Forced Diuresis with Neutral Fluid Balance During Cardiac Surgery, a Randomized Controlled Trial
- ClinicalTrials.gov ID
- NCT06886191
- Acronym / sponsor ID
- PURE / PUREstudy
- Conditions
- Cardiac Surgery Subjects
- Keywords
- renal oxygenation, urine oxygen tension, furosemide, balanced diuresis
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Sahlgrenska University HospitalUniversity, hospital or other
- Study start
- 17 Mar 2025 (estimated)
- Primary completion
- 31 Dec 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 20 Mar 2025 (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.
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
- Group difference in mean PuO2 before, during and after CPB
- Group difference in time weighted area under the curve for PuO2
- Group differences in renal near infrared spectroscopy (NIRS) before, during and after CPB
- Group difference in urine and blood biochemistry including renal biomarkers
- Group difference in urine output and fluid balance during surgery and first postoperative day
- Group differences in postoperative AKI according to the KDIGO criteria
- Time (minutes) with puO2 ≤ 15 and ≤ 10 mmHg during and after CPB
- 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.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| RenalGuard (RG) | Experimental | Device: RenalGuard TherapyThe RG system is used to ensure neutral (0) fluid balance while maintaining a urine flow >200 ml/hour. Urine output is replaced 1:1 with Plasmolyte solution. In patients randomized to RG, therapy is initiated after baseline measurements but before the start of surgery. If baseline urine flow is < 200 ml/hour, a bolus dose of furosemide (20 mg iv) is given, and additional furosemide bolus and/or titration of continuous furosemide infusion may be given to maintain urine flow rate >200ml/hour. After completed surgery, RG therapy continues until 3 hours after weaning from CPB |
| Standard of Care | No intervention | –Conduct of cardiopulmonary bypass will be done according to local clinical practice |
Who may qualify
- Ages
- 18 to 85 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- 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
Key exclusion criteria (5 listed)
- 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
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 |
|---|---|---|
| RenalGuard TherapyFluid management system, which weighs urine and controls intravenous administration of crystalloid solution. | Device | RenalGuard (RG) |
Primary outcome
Delta PuO2
Time frame: 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)
4 secondary outcomes
Repeated PuO2
Time frame: baseline, 30, 45 minutes on CPB and at 30, 60 and 240 minutes after CPB
PuO2 AUC
Time frame: From baseline before start of surgery until 4 hours after CPB
PuO2 sub threshold
Time frame: From baseline before surgery until 4 hours after CPB
Diuresis and fluid balance
Time frame: 24 hours
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 20 Mar 2025.
- Individual participant dataSharing planned: Undecided. Parts of the data may be analyzed in other projects
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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.
Lukas Lannemyr Lannemyr, MD, PhD principal investigator
Institute of Clinical Sciences, Dept of Anesthesia and Intensive Care, Sahlgrenska Academy, Gothenburg University. Gothenburg, Sweden
Questions about this trial
What is this clinical trial studying?
A study testing RenalGuard Therapy in people with Cardiac Surgery Subjects, run by Sahlgrenska University Hospital.
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 3 inclusion and 5 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 20 Mar 2025. Status can change between updates, so confirm with the study contact before making plans.
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 Lukas Lannemyr Lannemyr, MD, PhD (0046 708350971, lukas.lannemyr@vgregion.se), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Delta PuO2 (time frame: Baseline (before start of surgery) to 45 minutes after start of CPB). 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 20 Mar 2025.