PuO2 in RenalGuard Pilot Study

NCT06886191 | Not Yet Recruiting FDA Device

• 1 other identifier: PUREstudy
• Study Type: interventional
• Target: 30
• Locations: 0 countries
• Sites: N/A

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. 1.Group difference in mean PuO2 before, during and after CPB
2. 2.Group difference in time weighted area under the curve for PuO2
3. 3.Group differences in renal near infrared spectroscopy (NIRS) before, during and after CPB
4. 4.Group difference in urine and blood biochemistry including renal biomarkers
5. 5.Group difference in urine output and fluid balance during surgery and first postoperative day
6. 6.Group differences in postoperative AKI according to the KDIGO criteria
7. 7.Time (minutes) with puO2 ≤ 15 and ≤ 10 mmHg during and after CPB
8. 8.Dynamics of PuO2 during the early postoperative phase

Conditions

Cardiac Surgery Subjects

Keywords

renal oxygenation; urine oxygen tension; furosemide; balanced diuresis

Outcome Measures

Primary Outcomes (1)

• 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)

  Baseline (before start of surgery) to 45 minutes after start of CPB

Secondary Outcomes (4)

• Repeated PuO2

  baseline, 30, 45 minutes on CPB and at 30, 60 and 240 minutes after CPB

• PuO2 AUC

  From baseline before start of surgery until 4 hours after CPB

• PuO2 sub threshold

  From baseline before surgery until 4 hours after CPB

• Diuresis and fluid balance

  24 hours

Other Outcomes (4)

• Dynamics of PuO2 during the early postoperative phase

  24 hours

• Urine Nephrocheck

  4 hours after CPB

• Renal near-infrared spectroscopy (NIRS)

  From baseline before surgery until 4 hours after CPB

Study Arms (2)

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

Device: RenalGuard Therapy

Standard of Care

NO INTERVENTION

Conduct of cardiopulmonary bypass will be done according to local clinical practice

Interventions

RenalGuard Therapy DEVICE

Fluid management system, which weighs urine and controls intravenous administration of crystalloid solution.

RenalGuard (RG)

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• Sahlgrenska University Hospital: lead

Study Officials

• Lukas Lannemyr Lannemyr, MD, PhD

  Institute of Clinical Sciences, Dept of Anesthesia and Intensive Care, Sahlgrenska Academy, Gothenburg University. Gothenburg, Sweden

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Lukas Lannemyr Lannemyr, MD, PhD

CONTACT

0046 708350971; lukas.lannemyr@vgregion.se

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Consultant Anesthesiologist, MD, PhD

Study Record Dates

• First Submitted: March 10, 2025
• First Posted: March 20, 2025
• Study Start: March 17, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: March 20, 2025

Record last verified: 2025-03