Liver CirrhosisNCT07658794
Intraoperative Assessment of Microcirculatory Function Using Vascular Occlusion Test During Liver Transplantation
An observational study of Liver Cirrhosis and Early Allograft Dysfunction, run by Ippokrateio General Hospital of Thessaloniki at 1 site in Greece.
Trial summary
Early allograft dysfunction (EAD) remains one of the most important complications following orthotopic liver transplantation (OLT). Currently, there is no established intraoperative biomarker that reliably predicts graft dysfunction at an early stage. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Liver Cirrhosis, Early Allograft Dysfunction
- How many people
- 50 participants
- Where
- 1 siteGreece
- Study dates
- Jun 2026to Jun 2027
- How long will I take part?
- 30 Days
- 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 Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: The study population will consist of adult patients undergoing orthotopic liver transplantation at the participating center. Eligible patients will be enrolled before surgery and monitored intraoperatively using Near-Infrared Spectroscopy during standardized Vascular Occlusion Tests. The cohort will include liver transplant recipients managed according to standard institutional anesthetic, surgical and postoperative care protocols
Who may be able to join
- Adult patients aged 18 years or older
- Patients scheduled to undergo orthotopic liver transplantation
- Ability to obtain intraoperative Near-Infrared Spectroscopy measurements
- Written informed consent obtained before enrollment
Who cannot join
- Age younger than 18 years
- Refusal or inability to provide informed consent
- Emergency liver transplantation without sufficient time for enrollment
- Inability to perform the Vascular Occlusion Test or obtain reliable NIRS measurements
- Severe peripheral vascular disease or local upper-limb conditions interfering with monitoring
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Greece1 site
Ippokrateio General Hospital of Thessaloniki
Thessaloniki, Thessaloniki, 54642
Dimitrios Zafeiriadis, MD, +306980422306 ext. +30, imdzaf@gmail.com
About this study
Official title: The Predictive Value of the Vascular Occlusion Test During Orthotopic Liver Transplantation for the Development of Early Allograft Dysfunction
Early allograft dysfunction (EAD) remains one of the most important complications following orthotopic liver transplantation (OLT). Currently, there is no established intraoperative biomarker that reliably predicts graft dysfunction at an early stage. Near-infrared spectroscopy (NIRS) combined with the vascular occlusion test (VOT) is a non-invasive method for assessing tissue oxygenation and microcirculatory reserve. This prospective observational study aims to investigate whether VOT-derived parameters, including desaturation slope, recovery slope and post-ischemic hyperemic area under the curve (AUC-H), can predict EAD in liver transplant recipients. Measurements will be performed at four predefined intraoperative timepoints: after induction of anesthesia, during the anhepatic phase, during the neohepatic phase and at the end of surgery. The primary outcome is the occurrence of EAD according to Olthoff criteria.
Read the detailed description
Orthotopic liver transplantation (OLT) is the treatment of choice for patients with end-stage liver disease and acute liver failure. Despite advances in surgical technique and perioperative management, early allograft dysfunction (EAD) remains a common postoperative complication associated with increased morbidity, prolonged intensive care unit stay and reduced graft survival.
Increasing evidence suggests that microcirculatory dysfunction may play a pivotal role in the pathophysiology of ischemia-reperfusion injury and graft dysfunction after OLT. In contrast to conventional macrocirculatory monitoring, microcirculatory assessment provides direct information regarding tissue oxygenation, endothelial function and the adequacy of oxygen delivery at the cellular level.
Near-infrared spectroscopy (NIRS) combined with the vascular occlusion test (VOT) is a non-invasive and well-established technique for evaluating microvascular reactivity. During VOT, transient arterial occlusion is induced using a pneumatic cuff, while tissue oxygen saturation (StO₂) is continuously recorded. Parameters derived from the test include the desaturation slope (downslope), the recovery slope (upslope) and the area under the post-ischemic hyperemic curve (AUC-H), reflecting tissue oxygen consumption, endothelial function and microvascular reserve, respectively.
The present study is a prospective, single-center observational cohort study aiming to investigate the prognostic value of VOT-derived parameters in liver transplant recipients. VOT measurements will be performed at four predefined intraoperative timepoints: following induction of anesthesia (baseline), during the anhepatic phase, during the neohepatic phase after graft reperfusion, and at the end of surgery.
The primary endpoint is the occurrence of early allograft dysfunction according to the Olthoff criteria. Secondary outcomes include intensive care unit length of stay, hospital length of stay, duration of mechanical ventilation and established liver transplant outcome scores including L-GrAFT, EASE and EASIX.
In addition, exploratory analyses will investigate the relationship between VOT-derived parameters normalized to oxygen delivery (DO₂ and DO₂I) and postoperative outcomes, aiming to determine whether microcirculatory reserve adjusted for systemic oxygen transport provides superior prognostic information.
- Conditions
- Liver Cirrhosis, Early Allograft Dysfunction
- Keywords
- Vascular Occlusion Test, Near-Infrared Spectroscopy, Early Allograft Dysfunction, Liver Transplantation, Microcirculation
- Medical subject headings
- Liver Cirrhosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Adult Liver Transplant Recipients Undergoing Intraoperative VOT/NIRS Monitoring | Adult patients undergoing orthotopic liver transplantation will be enrolled in this observational cohort. During surgery, they will undergo standardized Vascular Occlusion Tests using Near-Infrared Spectroscopy to assess peripheral tissue oxygen saturation and microcirculatory reactivity. Measurements will be performed at predefined intraoperative timepoints, including baseline, anhepatic, neohepatic and final phases. Reoxygenation slope, hyperemic area under the curve and related parameters will be analyzed for their association with early allograft dysfunction and postoperative outcomes. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Early Allograft Dysfunction Within 7 Days After Liver Transplantation
Development of early allograft dysfunction after liver transplantation, defined according to established postoperative biochemical criteria, including elevated transaminases within the first 7 postoperative days, impaired coagulation, or hyperbilirubinemia.
Measured: Within 7 days after liver transplantation
Early Allograft Dysfunction
Development of early allograft dysfunction after liver transplantation, defined according to established postoperative biochemical criteria, including elevated transaminases within the first 7 postoperative days, impaired coagulation, or hyperbilirubinemia.
Measured: Within 7 days after liver transplantation
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Jun 2026
- Study startJun 2026 (estimated)
- Primary completionMar 2027 (estimated)
- Study completionJun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Liver CirrhosisStudies 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
- 50 participants (estimated)
- Target duration
- 30 Days
Sponsor and investigators
- Lead sponsor
- Ippokrateio General Hospital of Thessaloniki
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Dimitrios Zafeiriadis, Ippokrateio General Hospital of Thessaloniki
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07658794
- Sponsor's protocol ID
- ΕΣ:87/18-3-2026
- Status last verified
- Jun 2026
- First submitted
- 15 Jun 2026
- Last updated
- 1 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 1 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Predictive Value of the Vascular Occlusion Test During Orthotopic Liver Transplantation for the Development of Early Allograft Dysfunction
- ClinicalTrials.gov ID
- NCT07658794
- Acronym / sponsor ID
- ΕΣ:87/18-3-2026
- Conditions
- Liver Cirrhosis, Early Allograft Dysfunction
- Keywords
- Vascular Occlusion Test, Near-Infrared Spectroscopy, Early Allograft Dysfunction, Liver Transplantation, Microcirculation
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 50 participants (estimated)
- Lead sponsor
- Ippokrateio General Hospital of ThessalonikiUniversity, hospital or other
- Study start
- Jun 2026 (estimated)
- Primary completion
- Mar 2027 (estimated)
- Study completion
- Jun 2027 (estimated)
- First posted
- 22 Jun 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.
Early allograft dysfunction (EAD) remains one of the most important complications following orthotopic liver transplantation (OLT). Currently, there is no established intraoperative biomarker that reliably predicts graft dysfunction at an early stage. Near-infrared spectroscopy (NIRS) combined with the vascular occlusion test (VOT) is a non-invasive method for assessing tissue oxygenation and microcirculatory reserve. This prospective observational study aims to investigate whether VOT-derived parameters, including desaturation slope, recovery slope and post-ischemic hyperemic area under the curve (AUC-H), can predict EAD in liver transplant recipients. Measurements will be performed at four predefined intraoperative timepoints: after induction of anesthesia, during the anhepatic phase, during the neohepatic phase and at the end of surgery. The primary outcome is the occurrence of EAD according to Olthoff criteria.
Detailed description
Orthotopic liver transplantation (OLT) is the treatment of choice for patients with end-stage liver disease and acute liver failure. Despite advances in surgical technique and perioperative management, early allograft dysfunction (EAD) remains a common postoperative complication associated with increased morbidity, prolonged intensive care unit stay and reduced graft survival.
Increasing evidence suggests that microcirculatory dysfunction may play a pivotal role in the pathophysiology of ischemia-reperfusion injury and graft dysfunction after OLT. In contrast to conventional macrocirculatory monitoring, microcirculatory assessment provides direct information regarding tissue oxygenation, endothelial function and the adequacy of oxygen delivery at the cellular level.
Near-infrared spectroscopy (NIRS) combined with the vascular occlusion test (VOT) is a non-invasive and well-established technique for evaluating microvascular reactivity. During VOT, transient arterial occlusion is induced using a pneumatic cuff, while tissue oxygen saturation (StO₂) is continuously recorded. Parameters derived from the test include the desaturation slope (downslope), the recovery slope (upslope) and the area under the post-ischemic hyperemic curve (AUC-H), reflecting tissue oxygen consumption, endothelial function and microvascular reserve, respectively.
The present study is a prospective, single-center observational cohort study aiming to investigate the prognostic value of VOT-derived parameters in liver transplant recipients. VOT measurements will be performed at four predefined intraoperative timepoints: following induction of anesthesia (baseline), during the anhepatic phase, during the neohepatic phase after graft reperfusion, and at the end of surgery.
The primary endpoint is the occurrence of early allograft dysfunction according to the Olthoff criteria. Secondary outcomes include intensive care unit length of stay, hospital length of stay, duration of mechanical ventilation and established liver transplant outcome scores including L-GrAFT, EASE and EASIX.
In addition, exploratory analyses will investigate the relationship between VOT-derived parameters normalized to oxygen delivery (DO₂ and DO₂I) and postoperative outcomes, aiming to determine whether microcirculatory reserve adjusted for systemic oxygen transport provides superior prognostic information.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Target follow-up
- 30 Days
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Adult Liver Transplant Recipients Undergoing Intraoperative VOT/NIRS Monitoring | – | –Adult patients undergoing orthotopic liver transplantation will be enrolled in this observational cohort. During surgery, they will undergo standardized Vascular Occlusion Tests using Near-Infrared Spectroscopy to assess peripheral tissue oxygen saturation and microcirculatory reactivity. Measurements will be performed at predefined intraoperative timepoints, including baseline, anhepatic, neohepatic and final phases. Reoxygenation slope, hyperemic area under the curve and related parameters will be analyzed for their association with early allograft dysfunction and postoperative outcomes. |
Who may qualify
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
- Study population
- The study population will consist of adult patients undergoing orthotopic liver transplantation at the participating center. Eligible patients will be enrolled before surgery and monitored intraoperatively using Near-Infrared Spectroscopy during standardized Vascular Occlusion Tests. The cohort will include liver transplant recipients managed according to standard institutional anesthetic, surgical and postoperative care protocols
Key inclusion criteria (4 listed)
- Adult patients aged 18 years or older
- Patients scheduled to undergo orthotopic liver transplantation
- Ability to obtain intraoperative Near-Infrared Spectroscopy measurements
- Written informed consent obtained before enrollment
Key exclusion criteria (5 listed)
- Age younger than 18 years
- Refusal or inability to provide informed consent
- Emergency liver transplantation without sufficient time for enrollment
- Inability to perform the Vascular Occlusion Test or obtain reliable NIRS measurements
- Severe peripheral vascular disease or local upper-limb conditions interfering with monitoring
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Incidence of Early Allograft Dysfunction Within 7 Days After Liver Transplantation
Time frame: Within 7 days after liver transplantation
Development of early allograft dysfunction after liver transplantation, defined according to established postoperative biochemical criteria, including elevated transaminases within the first 7 postoperative days, impaired coagulation, or hyperbilirubinemia.
Early Allograft Dysfunction
Time frame: Within 7 days after liver transplantation
Development of early allograft dysfunction after liver transplantation, defined according to established postoperative biochemical criteria, including elevated transaminases within the first 7 postoperative days, impaired coagulation, or hyperbilirubinemia.
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 1 Jul 2026.
- Individual participant dataSharing planned: No
Related trials for Liver Cirrhosis
Not yet recruitingObservational study
A Study of Fatigue, Itching and Daily Activities in People With Primary Biliary Cholangitis Starting Elafibranor
Primary Biliary Cholangitis (PBC)
RecruitingPhase 1/2
Nitazoxanide in Spontaneous Bacterial Peritonitis
SBP - Spontaneous Bacterial Peritonitis
RecruitingPhase 3
Fenofibrate for Patients With Primary Biliary Cirrhosis Who Had An Inadequate Response to Ursodeoxycholic Acid
Primary Biliary Cirrhosis
RecruitingPhase 1/2
N-Acetylcysteine in the Management of Spontaneous Bacterial Peritonitis
SBP - Spontaneous Bacterial Peritonitis
RecruitingPhase 2/3
Fenofibrate in Patients With Primary Biliary Cholangitis (PBC)
Primary Biliary Cholangitis
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 Liver Cirrhosis and Early Allograft Dysfunction, run by Ippokrateio General Hospital of Thessaloniki at 1 site in Greece.
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 4 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 1 Jul 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 Greece. 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?
Contact Dimitrios Zafeiriadis, MD (+306980422306 ext. +30, imdzaf@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Early Allograft Dysfunction Within 7 Days After Liver Transplantation (time frame: Within 7 days after liver transplantation). The study lists 2 primary outcomes in all. 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 1 Jul 2026.