Trial Review

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
Help: Registration number
ACTRN12626001269325
Ethics application status
Help: Ethics application status
Approved
Date submitted
Help: Date submitted
13/08/2026
Date registered
Help: Date registered
22/10/2026
Date last updated
Help: Date last updated
22/10/2026
Date data sharing statement initially provided
Help: Data sharing statement date
22/10/2026
Type of registration
Help: Type of registration
Retrospectively registered

Titles & IDs
Public title
Using Doppler ultrasound to study blood flow in vessels outside the skull in critically ill patients in intensive care with suspected disturbed blood flow to the brain
Scientific title
Prospective Observational Pilot Study of the Arterial and Venous Extracranial Collateral Circulation Using Pulsed Wave Doppler in Intensive Care Unit Patients with Suspected Disturbed Cerebral Haemodynamics
Additional trial identifiers [1] 318176 0
ERM ID Number: 127183
Universal Trial Number (UTN)
Trial acronym
Related trial records

Health condition
Health condition(s) studied:
cerebral haemodynamics in critically ill patients 343232 0
stroke 343717 0
Condition category
Condition code
Neurological 339336 339336 0 0
Other neurological disorders
Stroke 339337 339337 0 0
Ischaemic
Stroke 339338 339338 0 0
Haemorrhagic

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of the intervention or exposure
Participants will undergo non-invasive pulsed wave Doppler ultrasound assessment of selected superficial extracranial arterial and venous vessels. Vessels assessed may include the superficial temporal artery and vein and vessels in the supraorbital/supratrochlear region.

Doppler assessments will be undertaken by the intensive care consultant undertaking the study and will measure waveform characteristics including direction of flow, peak systolic velocity, end-diastolic velocity, mean velocity, pulsatility index, resistive index, acceleration, acceleration time and other spectral waveform characteristics.

Ultrasound examinations will be performed using standard commercially available ultrasound equipment. Assessments are cutaneous and will not involve trans-orbital insonation.

Participants may undergo up to three Doppler assessment sessions during the first seven days following study enrolment. Each assessment is expected to take approximately 30 minutes. Undertaken up to 3 times while in ICU.

Clinical information relating to cerebral haemodynamics, neurological diagnosis, intracranial pressure where clinically available, physiological variables and clinical outcomes will be obtained from the medical record.

No treatment or clinical management decisions will be determined by the study measurements.
Intervention code [1] 335069 0
Diagnosis / Prognosis
Description of the comparator or control
Doppler findings will be compared between participants according to clinical characteristics, including neurological diagnosis and the presence or absence of abnormal cerebral haemodynamics.

Control group is comprised of healthy volunteers with normal brain, these volunteers will undergo a single doppler assessment over 30 minutes, undertaken by the principle investigator an intensive care consultant. This will be undertaken in the ICU's research area.
Control group
Active

Outcomes
Primary outcome [1] 346544 0
Feasibility of obtaining adequate extracranial arterial and/or venous Doppler signals in critically ill patients.
Timepoint [1] 346544 0
During each Doppler assessment session, with up to three assessment sessions performed during the hospital stay
Secondary outcome [1] 466337 0
Extracranial Doppler waveform characteristics between patients with or without intracranial hypertension
Timepoint [1] 466337 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [2] 469421 0
Extracranial Doppler waveform characteristic peak systolic velocity
Timepoint [2] 469421 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [3] 469422 0
Extracranial Doppler waveform characteristic end diastolic velocity
Timepoint [3] 469422 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [4] 469423 0
Extracranial Doppler waveform characteristic direction of blood flow
Timepoint [4] 469423 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [5] 469424 0
Extracranial Doppler waveform characteristic mean doppler velocity
Timepoint [5] 469424 0
During each Doppler assessment session, with up to three assessment sessions performed during the hospital stay
Secondary outcome [6] 469425 0
Extracranial Doppler waveform characteristic doppler acceleration
Timepoint [6] 469425 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [7] 469426 0
Extracranial Doppler waveform characteristic mean doppler velocity
Timepoint [7] 469426 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [8] 469427 0
Extracranial Doppler waveform characteristic resistive index
Timepoint [8] 469427 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [9] 469428 0
Extracranial Doppler waveform characteristic pulsatility index
Timepoint [9] 469428 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.
Secondary outcome [10] 469429 0
Extracranial Doppler waveform characteristic acceleration time
Timepoint [10] 469429 0
During each Doppler assessment session, with up to three assessment sessions performed over the 7 days from enrolment if still in hospital.

Eligibility
Key inclusion criteria
Age 18 years or older.
Admission to the intensive care unit.
Presence of a clinical condition associated with suspected or confirmed disturbance of cerebral haemodynamics, including one or more of the following:
cardiac or respiratory arrest;
intracranial haemorrhage;
acute ischaemic stroke;
traumatic brain injury;
suspected or confirmed raised intracranial pressure;
following cardiac or neurosurgical procedures; or
another acute condition where the treating clinical team considers disturbed cerebral haemodynamics may be present.
Consent obtained according to the ethically approved consent process, including participant consent, consent from the medical treatment decision maker, or another HREC-approved consent pathway where applicable.

A sub group of healthy volunteers will also be studied
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Healthy volunteers
Yes
Key exclusion criteria
Significant orbital trauma.
Recent orbital surgery that would preclude safe assessment.
Open craniofacial wounds preventing ultrasound assessment.
Severe haemodynamic instability such that the treating clinician considers participation inappropriate.
Treating clinician objection to participation.

Study design
Purpose
Natural history
Duration
Cross-sectional
Selection
Defined population
Timing
Prospective
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
16/05/2026
Date of last participant enrolment
Anticipated
16/05/2027
Actual
Date of last data collection
Anticipated
16/05/2027
Actual
Sample size
Target
50
Accrual to date
18
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 322741 0
Hospital
Name [1] 322741 0
Department of Critical Care at St.Vincents Hospital Melbourne'
Country [1] 322741 0
Australia
Primary sponsor type
Hospital
Name
St Vincent's Hospital Melbourne Melbourne, Victoria, Australia
Address
Country
Australia
Secondary sponsor category [1] 325663 0
None
Name [1] 325663 0
Address [1] 325663 0
Country [1] 325663 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 321180 0
St Vincent's Hospital Melbourne Human Research Ethics Committee
Ethics committee address [1] 321180 0
Ethics committee country [1] 321180 0
Australia
Date submitted for ethics approval [1] 321180 0
24/03/2026
Approval date [1] 321180 0
24/04/2026
Ethics approval number [1] 321180 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 152930 0
Dr Barry Dixon
Address 152930 0
St Vincent's Hospital Melbourne 41 Victoria Pde Fitzroy Victoria 3065
Country 152930 0
Australia
Phone 152930 0
+61 03 9231 4488
Fax 152930 0
Email 152930 0
[email protected]
Contact person for public queries
Name 152931 0
Barry Dixon
Address 152931 0
St Vincent's Hospital Melbourne 41 Victoria Pde Fitzroy Victoria 3065
Country 152931 0
Australia
Phone 152931 0
+61 03 9231 4488
Fax 152931 0
Email 152931 0
[email protected]
Contact person for scientific queries
Name 152932 0
Barry Dixon
Address 152932 0
St Vincent's Hospital Melbourne 41 Victoria Pde Fitzroy Victoria 3065
Country 152932 0
Australia
Phone 152932 0
+61 03 9231 4488
Fax 152932 0
Email 152932 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
Yes
Will there be any conditions when requesting access to individual participant data?
Persons/groups eligible to request access:
• Anyone
Conditions for requesting access:
• Yes, conditions apply:
• Requires a scientifically sound proposal or protocol
What individual participant data might be shared?
• All de-identified individual participant data
What types of analyses could be done with individual participant data?
• Any type of analysis (i.e. no restrictions on data re-use)
When can requests for individual participant data be made (start and end dates)?
From:
At the end of the study
To:
Not yet decided
Where can requests to access individual participant data be made, or data be obtained directly?
• Email of trial custodian, sponsor or committee: [email protected]

Are there extra considerations when requesting access to individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
ProtocolNo V1.3_Extracranial_Protocol-clean.docx

Documents added automatically
No additional documents have been identified.