Venous CongestionMICRO-CONGESTNCT07499401
Evaluation of the Microcirculatory Response to Fluids in Critically Ill Patients With Venous Congestion: A Prospective Observational Study
An observational study of Venous Congestion and Microcirculation, run by Università Politecnica delle Marche at 1 site in Italy.
Trial summary
The hypothesis is that fluid-responsive patients who show signs of venous congestion experience a worsening of microcirculatory status after fluid administration compared to patients without signs of venous congestion Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Venous Congestion, Microcirculation, Volume Expansion
- What is being tested?
- fluid challenge
- How many people
- 30 participants
- Where
- 1 siteItaly
- Study dates
- 15 Dec 2024to Jun 2026
- Phase
- Observational
- 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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Critically ill patients admitted to the intensive care unit
Who may be able to join
- Critically ill patients admitted to the intensive care unit
- Invasive or minimally invasive hemodynamic monitoring
Who cannot join
- Suspected or confirmed pregnancy
- Inability to access the oral cavity (e.g., facial trauma, oral bleeding)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Italy1 site, 1 recruiting
- Recruiting
AOU delle Marche
Ancona, Italy, 60123
Abele Donati Pr, PhD, +390715963858, a.donati@univpm.it
About this study
The hypothesis is that fluid-responsive patients who show signs of venous congestion experience a worsening of microcirculatory status after fluid administration compared to patients without signs of venous congestion
- Conditions
- Venous Congestion, Microcirculation, Volume Expansion
- Being tested
- fluid challenge
- Medical subject headings
- Hyperemia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
fluid challengeDrug
Signs of venous congestion and microcirculatory status will be assessed at baseline. A fluid challenge will then be performed, and microcirculation will be evaluated at the end of fluid administration and again after 30 minutes
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Sublingual total vessel density (TVD)
To compare changes in sublingual microcirculatory parameter - total vessel density (TVD) - before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Secondary outcomes (19)
Change in Sublingual percentage of perfused vessels (PPV)
To compare changes in sublingual microcirculatory parameter - percentage of perfused vessels (PPV) - before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual Microcirculatory Flow Index (MFI)
The primary objective of the study is to compare changes in sublingual microcirculation, measured by the Microcirculatory Flow Index (MFI), before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual perfused vessel density (PVD)
To compare changes in sublingual microcirculatory parameters - perfused vessel density (PVD) - before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual microcirculatory heterogeneity index (MHI)
To compare changes in sublingual microcirculatory parameters - microcirculatory heterogeneity index (MHI) - before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual PPV in Non-Preload-Dependent Patients With and Without Venous Congestion
To compare changes in sublingual PPV before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in non-preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual TVD in Non-Preload-Dependent Patients With and Without Venous Congestion
To compare changes in sublingual TVD before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in non-preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual MFI in Non-Preload-Dependent Patients With and Without Venous Congestion
To compare changes in sublingual MFI before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in non-preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual PVD in Non-Preload-Dependent Patients With and Without Venous Congestion
To compare changes in sublingual PVD before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in non-preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual MHI in Non-Preload-Dependent Patients With and Without Venous Congestion
To compare changes in sublingual MHI before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in non-preload-dependent patients with and without signs of venous congestion.
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and TVD in Critically Ill Patients and Subpopulations
- evaluate the relationship between signs of venous congestion TVD at baseline, after fluid administration, and 30 minutes post-fluid administration in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and PVD in Critically Ill Patients and Subpopulations
To evaluate the relationship between signs of venous congestion and PVD at baseline, after fluid administration, and 30 minutes post-fluid administration in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and MFI in Critically Ill Patients and Subpopulations
To evaluate the relationship between signs of venous congestion and MFI at baseline, after fluid administration, and 30 minutes post-fluid administration in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and PPV in Critically Ill Patients and Subpopulations
To evaluate the relationship between signs of venous congestion and PPV at baseline, after fluid administration, and 30 minutes post-fluid administration in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and MHI in Critically Ill Patients and Subpopulations
To evaluate the relationship between signs of venous congestion and MHI at baseline, after fluid administration, and 30 minutes post-fluid administration in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and TVD at Baseline
To evaluate the association between signs of venous congestion and TVD at baseline in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline
Association Between Venous Congestion and PVD at Baseline
To evaluate the association between signs of venous congestion and PVD at baseline in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline
Association Between Venous Congestion and MFI at Baseline
To evaluate the association between signs of venous congestion and MFI at baseline in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline
Association Between Venous Congestion and PPV at Baseline
To evaluate the association between signs of venous congestion and PPV at baseline in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline
Association Between Venous Congestion and MHI at Baseline
To evaluate the association between signs of venous congestion and MHI at baseline in critically ill patients and subgroups (e.g., septic shock).
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Mar 2026
- Study start15 Dec 2024
- Primary completionJun 2026 (estimated)
- Study completionJun 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Venous CongestionStudies 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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Università Politecnica delle Marche
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Abele Donati, MD, Università Politecnica delle Marche
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07499401
- Sponsor's protocol ID
- Prot. 2024 213
- Acronym
- MICRO-CONGEST
- Status last verified
- Mar 2026
- First submitted
- 18 Apr 2025
- Last updated
- 2 Apr 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 2 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of the Microcirculatory Response to Fluids in Critically Ill Patients With Venous Congestion: A Prospective Observational Study
- ClinicalTrials.gov ID
- NCT07499401
- Acronym / sponsor ID
- MICRO-CONGEST / Prot. 2024 213
- Conditions
- Venous Congestion, Microcirculation, Volume Expansion
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Università Politecnica delle MarcheUniversity, hospital or other
- Study start
- 15 Dec 2024 (actual)
- Primary completion
- Jun 2026 (estimated)
- Study completion
- Jun 2026 (estimated)
- First posted
- 30 Mar 2026 (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 hypothesis is that fluid-responsive patients who show signs of venous congestion experience a worsening of microcirculatory status after fluid administration compared to patients without signs of venous congestion
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Critically ill patients admitted to the intensive care unit
Key inclusion criteria (2 listed)
- Critically ill patients admitted to the intensive care unit
- Invasive or minimally invasive hemodynamic monitoring
Key exclusion criteria (2 listed)
- Suspected or confirmed pregnancy
- Inability to access the oral cavity (e.g., facial trauma, oral bleeding)
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 |
|---|---|---|
| fluid challengeSigns of venous congestion and microcirculatory status will be assessed at baseline. A fluid challenge will then be performed, and microcirculation will be evaluated at the end of fluid administration and again after 30 minutes | Drug | – |
Primary outcome
Change in Sublingual total vessel density (TVD)
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
To compare changes in sublingual microcirculatory parameter - total vessel density (TVD) - before fluid administration, immediately after volume expansion, and 30 minutes post-fluid administration in preload-dependent patients with and without signs of venous congestion.
19 secondary outcomes
Change in Sublingual percentage of perfused vessels (PPV)
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual Microcirculatory Flow Index (MFI)
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual perfused vessel density (PVD)
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual microcirculatory heterogeneity index (MHI)
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual PPV in Non-Preload-Dependent Patients With and Without Venous Congestion
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual TVD in Non-Preload-Dependent Patients With and Without Venous Congestion
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual MFI in Non-Preload-Dependent Patients With and Without Venous Congestion
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual PVD in Non-Preload-Dependent Patients With and Without Venous Congestion
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Change in Sublingual MHI in Non-Preload-Dependent Patients With and Without Venous Congestion
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and TVD in Critically Ill Patients and Subpopulations
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and PVD in Critically Ill Patients and Subpopulations
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and MFI in Critically Ill Patients and Subpopulations
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and PPV in Critically Ill Patients and Subpopulations
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and MHI in Critically Ill Patients and Subpopulations
Time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge
Association Between Venous Congestion and TVD at Baseline
Time frame: Baseline
Association Between Venous Congestion and PVD at Baseline
Time frame: Baseline
Association Between Venous Congestion and MFI at Baseline
Time frame: Baseline
Association Between Venous Congestion and PPV at Baseline
Time frame: Baseline
Association Between Venous Congestion and MHI at Baseline
Time frame: Baseline
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 2 Apr 2026.
- Individual participant dataSharing planned: Undecided
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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.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Venous Congestion and Microcirculation, run by Università Politecnica delle Marche at 1 site in Italy.
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 2 inclusion and 2 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: looking for participants now, as of the sponsor's last update on 2 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.
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?
Each site lists its own contact: choose the nearest one under Trial locations. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Sublingual total vessel density (TVD) (time frame: Baseline, immediately post-fluid challenge, and 30 minutes post-fluid challenge). 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 2 Apr 2026.