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Trial registered on ANZCTR


Registration number
ACTRN12622001330730
Ethics application status
Approved
Date submitted
14/09/2022
Date registered
14/10/2022
Date last updated
11/04/2024
Date data sharing statement initially provided
14/10/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
The role of nebulized sodium nitrite and argon on blood pressure and brain blood flow control
Scientific title
Elucidating the effects of nebulized sodium nitrite and argon on blood pressure and cerebrovascular haemodynamics in healthy adults and hypertensive patients
Secondary ID [1] 307627 0
Nil
Universal Trial Number (UTN)
U1111-1277-7574
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Hypertension 327111 0
Condition category
Condition code
Cardiovascular 324258 324258 0 0
Hypertension
Stroke 324942 324942 0 0
Ischaemic

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The participants will undergo 5 min nebulized sodium nitrite (45 mg & 90 mg) with a nebuliser mask and 2 hour argon gas inhalation (79% argon and 21% oxygen) with a mouthpiece in a single-blinded manner with a 7 day washout period. Research staff will be present to monitor adherence to the intervention. These doses have been shown to be safe in healthy cohorts as well as clinical groups.
Intervention code [1] 324427 0
Treatment: Drugs
Comparator / control treatment
This is a placebo-controlled cross-over design. For the nebulized sodium nitrite arm of the study, a saline placebo (normal saline) will be used. For the argon-inhalation arm of the study, room air will be used as placebo.
Control group
Placebo

Outcomes
Primary outcome [1] 332539 0
Resting brachial blood pressure using a automated digital sphygmomanometer (BP+)
Timepoint [1] 332539 0
For the nebulized sodium nitrite arm, brachial blood pressure will be assessed prior to intervention (i.e., baseline) and upon completion of the intervention (10 min - primary endpoint), and at hour 1 and 2 post completion of intervention.
For the argon gas inhalation arm, brachial blood pressure will be assessed prior to intervention (i.e., baseline) and at hour 1 and 2 during the intervention, with primary endpoint being hour 2.
Primary outcome [2] 332540 0
Global cerebral blood flow will be determined by measuring internal carotid artery and vertebral artery blood flows using duplex Doppler ultrasound
Timepoint [2] 332540 0
For the nebulized sodium nitrite arm, global cerebral blood flow will be assessed prior to intervention (i.e., baseline) and upon completion of the intervention (10 min - primary endpoint), and at hour 1 and 2 post completion of intervention.
For the argon gas inhalation arm, global cerebral blood flow will be assessed prior to intervention (i.e., baseline) and at hour 1 and 2 during the intervention, with primary endpoint being hour 2.
Secondary outcome [1] 413853 0
Middle cerebral artery velocity, assessed using transcranial Doppler ultrasound
Timepoint [1] 413853 0
For the nebulized sodium nitrite arm, middle cerebral artery velocity will be assessed prior to intervention (i.e., baseline) and upon completion of the intervention (10 min), and at hour 1 and 2 post completion of intervention.
For the argon gas inhalation arm, middle cerebral artery velocity will be assessed prior to intervention (i.e., baseline) and at hour 1 and 2 during the intervention.
Secondary outcome [2] 413854 0
Pulmonary ventilation assessing using heated pneumotachography
Timepoint [2] 413854 0
For the nebulized sodium nitrite arm, pulmonary ventilation will be assessed prior to intervention (i.e., baseline) and upon completion of the intervention (10 min), and at hour 1 and 2 post completion of intervention.
For the argon gas inhalation arm, pulmonary ventilation will be assessed prior to intervention (i.e., baseline) and at hour 1 and 2 during the intervention.

Eligibility
Key inclusion criteria
Patients with essential hypertension (At least Stage 2 hypertension; untreated office systolic blood pressure (SBP) greater than or equal to 140 mmHg or diastolic blood pressure (DBP_ greater than or equal to 90 mmHg);
Patients with chronic atrial fibrillation, as established on ECG or Holter monitoring
Normotensive controls (office SBP less than or equal to 120 mmHg and DBP less than or equal to 80 mmHg);
Aged over 18 years;
Body mass index less than 35 kg/m2.
Minimum age
18 Years
Maximum age
85 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Hemodynamically significant valvular heart disease (excluding atrial fibrillation e.g., stenosis, mechanical valve replacement)
Severe left ventricular systolic dysfunction
Recent acute coronary syndrome (<12 months) (e.g., myocardiac infarction, angioplasty, unstable angina)
Previous coronary artery bypass surgery
Secondary causes of hypertension (e.g., phaeochromocytoma)
Recent stroke/transient ischaemic attack (<12 months)
Current smoker
Body mass index <18 kg/m2.
Current pregnancy
Current user of recreational drugs
Current abuser of alcohol
Inability to fully or appropriately provide consent (e.g., language issue, reading capability)
Underlying medical conditions, which in the opinion of the Investigator place the participant at unacceptably high risk for participating in the study.
Chronic and systemic illness including:
Severe respiratory disease (e.g., chronic obstructive pulmonary disease);
Severe, uncontrolled type II diabetes;
Current treatment for cancer or complete remission <5 years
Connective tissue or inflammatory disease
Neurological / psychiatric disease (e.g., peripheral neuropathy, dementia, Parkisnon’s, epilepsy)
Infection or pyrexial illness
Uncontrolled thyroid disorders
Renal impairment (e.g., glomerulus filtration rate less than 60)
Liver disease

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomization will be performed by a statistician.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Crossover
Other design features
Phase
Phase 1 / Phase 2
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
1/11/2022
Actual
9/01/2023
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
80
Accrual to date
18
Final
Recruitment outside Australia
Country [1] 25009 0
New Zealand
State/province [1] 25009 0

Funding & Sponsors
Funding source category [1] 311892 0
Government body
Name [1] 311892 0
New Zealand Health Research Council
Country [1] 311892 0
New Zealand
Funding source category [2] 316285 0
Charities/Societies/Foundations
Name [2] 316285 0
Maurice Phyllis & Paykel Trust
Country [2] 316285 0
New Zealand
Primary sponsor type
University
Name
University of Auckland
Address
Auckland CBD, Auckland 1010
Country
New Zealand
Secondary sponsor category [1] 313774 0
None
Name [1] 313774 0
Address [1] 313774 0
Country [1] 313774 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311327 0
Central Health and Disability Ethics Committee
Ethics committee address [1] 311327 0
Ministry of Health
Health and Disability Ethics Committees
PO Box 5013
Wellington 6140
Ethics committee country [1] 311327 0
New Zealand
Date submitted for ethics approval [1] 311327 0
Approval date [1] 311327 0
01/08/2022
Ethics approval number [1] 311327 0

Summary
Brief summary
Although stroke is among the most common causes of mortality and morbidity in New Zealand, there is limited options for improving stroke outcome at the ambulance-level. We and others have recently shown nitric oxide (NO) and argon can significantly reduce infarct volume in animal models of ischaemic stroke. Building on this, the goal of this research is to identify novel treatments to improve patient outcome following stroke. Using brachial blood pressure (BP), duplex and transcranial Doppler sonography to measure cerebral blood flow (CBF), we will determine the effects of nebulized sodium nitrite (an NO donor) and argon inhalation on blood pressure control and cerebral haemodyanmics in healthy individuals and hypertensive patients. We will test the hypotheses that 1) nebulized sodium nitrite will enhance blood pressure and cerebral blood flow control; and 2) argon gas inhalation will not significantly impact blood pressure or cerebral blood flow. Insights gained from this research will lay the foundation for future clinical trials to examine the use of argon to slow the progression of brain injury, which will significantly improve how acute stroke is treated and managed within New Zealand.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 120726 0
Dr Mickey Fan
Address 120726 0
Faculty of Health and Medical Sciences
The University of Auckland
85 Park Road
Grafton
Auckland 1023
Country 120726 0
New Zealand
Phone 120726 0
+64 212968936
Fax 120726 0
Email 120726 0
mickey.fan@auckland.ac.nz
Contact person for public queries
Name 120727 0
Dr Mickey Fan
Address 120727 0
Faculty of Health and Medical Sciences
The University of Auckland
85 Park Road
Grafton
Auckland 1023
Country 120727 0
New Zealand
Phone 120727 0
+64 212968936
Fax 120727 0
Email 120727 0
mickey.fan@auckland.ac.nz
Contact person for scientific queries
Name 120728 0
Dr Mickey Fan
Address 120728 0
Faculty of Health and Medical Sciences
The University of Auckland
85 Park Road
Grafton
Auckland 1023
Country 120728 0
New Zealand
Phone 120728 0
+64 212968936
Fax 120728 0
Email 120728 0
mickey.fan@auckland.ac.nz

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
We currently do not have ethical approval for additional use of the IPD beyond the study


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
17119Ethical approval    384417-(Uploaded-14-09-2022-07-49-03)-Study-related document.pdf



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.