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Trial registered on ANZCTR


Registration number
ACTRN12624000766516
Ethics application status
Approved
Date submitted
27/05/2024
Date registered
24/06/2024
Date last updated
24/06/2024
Date data sharing statement initially provided
24/06/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
An investigation of Gas Flows during Preoxygenation with Nasal High Flow in volunteers
Scientific title
An investigation of Gas Flows during Preoxygenation with Nasal High Flow in volunteers
Secondary ID [1] 312224 0
None
Universal Trial Number (UTN)
U1111-1308-5523
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Preoxygenation 333921 0
Condition category
Condition code
Anaesthesiology 330591 330591 0 0
Anaesthetics
Respiratory 330692 330692 0 0
Normal development and function of the respiratory system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Healthy volunteer participants will be reclined on a hospital bed at 20 degrees in a laboratory setting. Two researchers will be present; one to operate the equipment and the other to monitor the participant.

Flow, generated by a computer-controlled flow source (custom, Fisher&Paykel Healthcare, New Zealand) will pass through a humidifier (950, Fisher & Paykel Healthcare, New Zealand) before being administered to the participant through a nasal interface, either a high flow interface (AA001, Fisher & Paykel Healthcare, New Zealand) or a low flow cannula (Hudson standard nasal tip, Teleflex, Morrisville, USA).

Tolerability Assessment:
An initial test will be performed to check the participant's tolerance to flow and mouth open/closed combinations by increasing flow (10, 25, 40, 55, 70 L/min) until either the flow reaches 70 L/min or the participant indicates it is not tolerable.

Measurements:
The participant will be fitted with a modified CPAP mask (FitLife Total, Phillips, Netherlands). A mouthpiece extends from the participant’s mouth through the body of the mask to atmosphere. This mouthpiece is modified from a commercially available spirometry mouthpiece (EasyOne, ndd Medizintechnik AG, Switzerland). An additional port provides a path for gas from inside the mask to atmosphere. It should be noted that there is always a gas path to atmosphere to ensure the participant can breathe.

Three flow meters (SFM3200-AW, Sensirion, Switzerland) are in the system. These flow meters measure the flow rate:
1. from the flow source,
2. entering or exiting the mouth through the mouthpiece and
3. entering/exiting the mask body through the port through the mask body.

The flow meters are sampled, and the results written to a file on the PC.

The flow-weighted FiO2 (the primary endpoint) can be calculated from these three flow readings

The following flow, cannula and mouth open/closed combinations will be administered for 120s per combination however the first 20s of data will be discarded as this has been set aside to allow the next set up to be established (i.e the 'washout' period of 20s is built into the 120s period and only the last 100s of data will be used for each combination).
o 10 L.min-1 through low flow cannula (Hudson standard nasal tip, Teleflex, Morrisville, USA )
o Flows through High Flow Nasal Oxygen (HFNO) cannula (Optiflow, Fisher & Paykel Healthcare, Auckland, New Zealand)
of :
o 10, 25, 40, 55, 70 L.min-1
with:
1. Mouth open
2. Mouth closed

This is a cross over study and each participant will receive all of the combinations (subject to finding these combinations tolerable).

We estimate the total time for a participant will be approximately 60 minutes.

The concentration of carbon dioxide in the mask body and the participant's oxygen saturation will be monitored for safety.
Intervention code [1] 328676 0
Prevention
Intervention code [2] 328754 0
Treatment: Devices
Comparator / control treatment
10 L.min-1 through low flow cannula, with mouth open (Standard care)
Control group
Active

Outcomes
Primary outcome [1] 338343 0
Flow-weighted mean fraction of inspired oxygen over 100s at flows of:
a) 10 L/min through low flow cannula (Hudson standard nasal tip, Teleflex, Morrisville, USA )
b) Flows through HFNO cannula (Optiflow, Fisher & Paykel Healthcare, Auckland, New Zealand) of :
10, 25, 40, 55, 70 L./min
with:
1. Mouth open
2. Mouth closed (achieved by placing a cap over the external exit of the mouth piece)

This endpoint will be assessed independently for each combination
Timepoint [1] 338343 0
Assessed continuously for 100 seconds during each intervention test
Secondary outcome [1] 435529 0
• Flow rates through the mouth and nose originating from:
o The participant
o the HFNO system

i.e. this outcome assesses where the flow from the HFNO system goes and where the flow to/from the patient goes. It is considered one outcome.
Timepoint [1] 435529 0
Assessed continuously for 100 seconds during each intervention test and then calculated
Secondary outcome [2] 435530 0
Continuous estimated FiO2
Timepoint [2] 435530 0
Assessed continuously for 100 seconds during each intervention test
Secondary outcome [3] 435531 0
Peak inspiratory demand through the mouth and / or nose
Timepoint [3] 435531 0
Assessed continuously for 100 seconds during each intervention test
Secondary outcome [4] 435532 0
Respiratory rate
Timepoint [4] 435532 0
Assessed continuously for 100 seconds during each intervention test
Secondary outcome [5] 435533 0
Tidal volume
Timepoint [5] 435533 0
Assessed continuously for 100 seconds during each intervention test
Secondary outcome [6] 435534 0
Lung volume change
Timepoint [6] 435534 0
Assessed continuously for 100 seconds during each intervention test
Secondary outcome [7] 435535 0
Tolerability (binary) to different flow combinations (flow rate and mouth open/closed)
Timepoint [7] 435535 0
We will assess tolerability to each flow with and without mouth closed for 30s per combination before fitting the measurement mask. Only tolerated flows will be assessed with the measurement mask. This is for participant comfort.
Secondary outcome [8] 435537 0
Compliance with each flow condition during measurement part of study
Timepoint [8] 435537 0
Assessed continuously for 100 seconds during each intervention test

Eligibility
Key inclusion criteria
Volunteer participants 16 years and over
capable of informed consent
Minimum age
16 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
HFNO contraindicated as per manufacturer’s instructions (AA001, Fisher & Paykel Healthcare, Auckland, New Zealand

Study design
Purpose of the study
Prevention
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 26337 0
New Zealand
State/province [1] 26337 0
Auckland

Funding & Sponsors
Funding source category [1] 316603 0
University
Name [1] 316603 0
University of Auckland
Country [1] 316603 0
New Zealand
Primary sponsor type
University
Name
University of Auckland
Address
Country
New Zealand
Secondary sponsor category [1] 318785 0
None
Name [1] 318785 0
Address [1] 318785 0
Country [1] 318785 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 315387 0
Central Health and Disability Ethics Committee
Ethics committee address [1] 315387 0
https://ethics.health.govt.nz/about/central-health-and-disability-ethics-committee/
Ethics committee country [1] 315387 0
New Zealand
Date submitted for ethics approval [1] 315387 0
Approval date [1] 315387 0
18/09/2023
Ethics approval number [1] 315387 0
2023 EXP 18477

Summary
Brief summary
This study is hypothesis generating and intended to characterise key variables during pre oxygenation with HFNO. The primary endpoint will be the flow-weighted mean fraction of inspired oxygen (FiO2) over 100s at flows of 10, 25, 40, 55, and 70 L.min-1 with i) the mouth open and ii) the mouth closed. To ensure these flows are tolerable to the participant, each combination will first be administered to the participant without the measurement apparatus in place. Only those combinations that are tolerable will then be administered in the main part of the study. Tolerance to flow combinations will be reported as a secondary outcome. Measurements at 10 L.min-1 will be performed with both HFNO prongs and standard low flow prongs, as the latter are commonly used in clinical practice.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 134542 0
Mr Matthew Payton
Address 134542 0
Daniell Building, Fisher & Paykel Healthcare, 15 Maurice Paykel Place, Auckland 2013
Country 134542 0
New Zealand
Phone 134542 0
+64 21 774 887
Fax 134542 0
Email 134542 0
matthew.payton@fphcare.co.nz
Contact person for public queries
Name 134543 0
Matthew Payton
Address 134543 0
Daniell Building, Fisher & Paykel Healthcare, 15 Maurice Paykel Place, Auckland 2013
Country 134543 0
New Zealand
Phone 134543 0
+64 21 774 887
Fax 134543 0
Email 134543 0
matthew.payton@fphcare.co.nz
Contact person for scientific queries
Name 134544 0
Matthew Payton
Address 134544 0
Daniell Building, Fisher & Paykel Healthcare, 15 Maurice Paykel Place, Auckland 2013
Country 134544 0
New Zealand
Phone 134544 0
+64 21 774 887
Fax 134544 0
Email 134544 0
matthew.payton@fphcare.co.nz

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

No Supporting Document Provided



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.