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Alterations of Conjunctival Microcirculation in Brain Dead Patients

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ClinicalTrials.gov Identifier: NCT02483273
Recruitment Status : Completed
First Posted : June 26, 2015
Last Update Posted : March 3, 2016
Sponsor:
Information provided by (Responsible Party):
Tomas Tamosuitis, Lithuanian University of Health Sciences

Brief Summary:
Study hypothesize that ocular microcirculation is reflecting cerebral perfusion. The purpose of this study is to evaluate ocular microcirculation in brain dead patients using side dark field (SDF) videomicroscope and compare it with microcirculatory parameters of healthy volunteers.

Condition or disease
Brain Death

Detailed Description:

Microcirculation videomicroscopy techniques are used to evaluate a global organ perfusion in various critical conditions using limited suitable sites available for visualisation. However, ocular microcirculation may become a window to specifically cerebral perfusion due to related blood supply, close anatomical proximity and easy accessibility for videomicroscopy. Cerebral perfusion mainly depends on cerebral flow and intracranial pressure and therefore we aim, for the first time, to demonstrate microcirculatory status of ocular conjunctiva in clinical conditions when cerebral flow is completely absent.

In a single center open label observational study investigators analyzed conjunctival and sublingual microcirculation using SDF videomicroscopy in brain dead patients after reaching systemic hemodynamic targets to optimise perfusion of donor organs. All brain death diagnoses were confirmed by cerebral angiography. Microcirculatory images obtained and analyzed using standardized published recommendations by experts in this field. Microcirculation of sublingual and conjunctival areas were recorded in matching number of healthy volunteers using same techniques.


Study Type : Observational
Actual Enrollment : 22 participants
Observational Model: Case Control
Time Perspective: Prospective
Official Title: Alterations of Conjunctival Microcirculation in Brain Dead Patients
Study Start Date : May 2011
Actual Primary Completion Date : September 2015
Actual Study Completion Date : March 2016

Group/Cohort
Brain dead patients
Brain dead patients certified by cerebral angiography.
Healthy volunteers
Any person with no known cerebral pathology.



Primary Outcome Measures :
  1. Microvascular flow index (MFI) of ocular conjunctiva. [ Time Frame: After confirmed diagnosis of brain death of any course using cerebral angiography at any time up to 24 hours. ]
    Conjunctival convective oxygen transport presented as MFI of small vessels mostly capillaries with diameter cutoff value of 20µm. Images of microcirculation were taken from at least three different points in each ocular conjunctiva and recorded for at least 20 seconds avoiding pressure artifacts. Microcirculation images were obtained using SDF videomicroscopy (Microscan®, Microvision Medicals, Amsterdam, Netherlands). Data recorded to the hard drive of personal computer using AVA 3.0v software (Microvision Medical, Amsterdam, Netherlands). Video clips were then randomly blinded and later analyzed by 2 independent investigators.

  2. Total vessel density (TVD) of ocular concunctiva. [ Time Frame: After confirmed diagnosis of brain death of any course using cerebral angiography at any time up to 24 hours. ]
    Conjunctival microvascular diffusion distance presented as TVD (mm/mm²) of small vessels mostly capillaries with diameter cutoff value of 20µm. Images of microcirculation were taken from at least three different points in each ocular conjunctiva and recorded for at least 20 seconds avoiding pressure artifacts. Microcirculation images were obtained using SDF videomicroscopy (Microscan®, Microvision Medicals, Amsterdam, Netherlands). Data recorded to the hard drive of personal computer using AVA 3.0v software (Microvision Medical, Amsterdam, Netherlands). Video clips were then randomly blinded and later analyzed by 2 independent investigators.

  3. Perfused vessel density (PVD) of ocular conjunctiva. [ Time Frame: After confirmed diagnosis of brain death of any course using cerebral angiography at any time up to 24 hours. ]
    Conjunctival microvascular diffusion distance presented as PVD (mm/mm²) of small vessels mostly capillaries with diameter cutoff value of 20µm. Images of microcirculation were taken from at least three different points in each ocular conjunctiva and recorded for at least 20 seconds avoiding pressure artifacts. Microcirculation images were obtained using SDF videomicroscopy (Microscan®, Microvision Medicals, Amsterdam, Netherlands). Data recorded to the hard drive of personal computer using AVA 3.0v software (Microvision Medical, Amsterdam, Netherlands). Video clips were then randomly blinded and later analyzed by 2 independent investigators


Secondary Outcome Measures :
  1. Microvascular flow index (MFI) of sublingual mucosa. [ Time Frame: After confirmed diagnosis of brain death of any course using cerebral angiography at any time up to 24 hours. ]
    Sublingual mucosa convective oxygen transport presented as MFI of small vessels mostly capillaries with diameter cutoff value of 20µm. Images of microcirculation were taken from at least three different points in sublingual mucosa and recorded for at least 20 seconds avoiding pressure artifacts. Microcirculation images were obtained using SDF videomicroscopy (Microscan®, Microvision Medicals, Amsterdam, Netherlands). Data recorded to the hard drive of personal computer using AVA 3.0v software (Microvision Medical, Amsterdam, Netherlands). Video clips were then randomly blinded and later analyzed by 2 independent investigators.

  2. Total vessel density (TVD) of sublingual mucosa. [ Time Frame: After confirmed diagnosis of brain death of any course using cerebral angiography at any time up to 24 hours. ]
    Sublingual mucosa microvascular diffusion distance presented as TVD (mm/mm²) of small vessels mostly capillaries with diameter cutoff value of 20µm. Images of microcirculation were taken from at least three different points in sublingual mucosa and recorded for at least 20 seconds avoiding pressure artifacts. Microcirculation images were obtained using SDF videomicroscopy (Microscan®, Microvision Medicals, Amsterdam, Netherlands). Data recorded to the hard drive of personal computer using AVA 3.0v software (Microvision Medical, Amsterdam, Netherlands). Video clips were then randomly blinded and later analyzed by 2 independent investigators.

  3. Perfused vessel density (PVD) of sublingual mucosa. [ Time Frame: After confirmed diagnosis of brain death of any course using cerebral angiography at any time up to 24 hours. ]
    Sublingual mucosa microvascular diffusion distance presented as PVD (mm/mm²) of small vessels mostly capillaries with diameter cutoff value of 20µm. Images of microcirculation were taken from at least three different points in sublingual mucosa and recorded for at least 20 seconds avoiding pressure artifacts. Microcirculation images were obtained using SDF videomicroscopy (Microscan®, Microvision Medicals, Amsterdam, Netherlands). Data recorded to the hard drive of personal computer using AVA 3.0v software (Microvision Medical, Amsterdam, Netherlands). Video clips were then randomly blinded and later analyzed by 2 independent investigators.



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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
All single center tertiary level Neurosurgery Intensive Care unit patients angiographically confirmed brain dead.
Criteria

Inclusion Criteria:

  • Diagnosed brain dead

Exclusion Criteria:

  • Conjunctival or sublingual mucosa damage

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02483273


Locations
Lithuania
Lithuanian University of Health Sciences
Kaunas, Lithuania
Sponsors and Collaborators
Lithuanian University of Health Sciences
Investigators
Principal Investigator: Vidas Pilvinis, MD,PhD Lithuanian UHS Intensive Care Clinic

Publications:

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Tomas Tamosuitis, Lithuanian University of Health Sciences Intensive Care Clinic Research Fellow, Lithuanian University of Health Sciences
ClinicalTrials.gov Identifier: NCT02483273     History of Changes
Other Study ID Numbers: P1-BE-2-19/2011
First Posted: June 26, 2015    Key Record Dates
Last Update Posted: March 3, 2016
Last Verified: March 2016
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided

Keywords provided by Tomas Tamosuitis, Lithuanian University of Health Sciences:
Conjunctival microcirculation
Sublingual microcirculation
Sidestream Dark Field (SDF) microscopy

Additional relevant MeSH terms:
Brain Death
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Coma
Unconsciousness
Consciousness Disorders
Neurobehavioral Manifestations
Neurologic Manifestations
Death
Pathologic Processes