Venous congestion and microcirculation after elective cardiac surgery

Association of Microcirculation, Vexus Score and Femoral Vein Doppler in Patients on the ICU After Non-emergency Cardiac Surgery

Observational University Hospital, Basel, Switzerland · NCT07052461

This project will try to see if bedside ultrasound signs of venous congestion (VEXUS score and femoral vein Doppler) are linked with microcirculatory problems in adults during their ICU stay after elective or urgent cardiac surgery.

Quick facts

Study typeObservational
Enrollment40 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity Hospital, Basel, Switzerland Academic / other
Locations1 site (Basel)
Trial IDNCT07052461 on ClinicalTrials.gov

What this trial studies

This observational cohort will follow adults who have elective or urgent cardiac surgery during their postoperative ICU stay to explore links between venous congestion and microcirculatory function. Investigators will use bedside ultrasound measures — including the VEXUS score and femoral vein Doppler — alongside bedside microcirculatory assessments to compare sonographic signs of venous congestion with microvascular perfusion. Patients with severe chronic kidney disease, transplants, pregnancy, emergency surgery, or conditions preventing Doppler imaging will be excluded. Data will be collected during the immediate postoperative ICU period to determine whether sonographic congestion correlates with impaired microcirculation and clinical outcomes such as acute kidney injury.

Who should consider this trial

Good fit: Adults aged 18 or older undergoing elective or urgent cardiac surgery who will require postoperative ICU care and can give informed consent, without severe CKD, organ transplants, pregnancy, or conditions that prevent Doppler imaging.

Not a fit: Patients undergoing emergency cardiac surgery, people with severe chronic kidney disease or on dialysis, prior renal or liver transplant recipients, pregnant women, or those with abdominal conditions that prevent Doppler imaging are excluded and unlikely to benefit from this protocol.

Why it matters

Potential benefit: If the link is confirmed, these non-invasive ultrasound signs could help clinicians recognize patients at risk of microcirculatory impairment and organ dysfunction, supporting more tailored fluid and hemodynamic management.

How similar studies have performed: Previous research has linked venous congestion and elevated CVP to worse renal outcomes and small studies have used VEXUS and femoral vein Doppler, but direct evidence tying these sonographic signs to microcirculatory impairment is limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age ≥ 18 years
* Elective or urgent (need for definitive procedure during hospitalisation, but not emergency intervention) cardiac surgery

Exclusion Criteria:

* Age \< 18 years
* Pregnant women
* Known severe chronic kidney disease (estimated glomerular filtration rate \<15 mL/min per 1.73 m2 or dialysis)
* Renal or liver transplantation
* Any known condition interfering with Doppler evaluation of the portal system (including known or suspected cirrhosis or portal vein thrombosis or huge abdominal emphysema).
* Inability to consent to study
* Emergency cardiac surgery

Where this trial is running

Basel

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Microcirculatory DiffusionMicrocirculatory Convection CapacityVenous CongestionPostoperative Cardiac SurgeryFluid ManagementHaemodynamic Coherencevexus scorefemoral vein doppler
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.