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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
A study of super-high flow oxygen therapy in healthy volunteers and its effect on the lungs - the SHOT study
Scientific title
A study in healthy volunteers to describe the airway pressures generated by a wide range of flows provided by high flow humidified nasal oxygen therapy and the effect on regional lung ventilation
Secondary ID [1] 281708 0
Universal Trial Number (UTN)
Trial acronym
The SHOT study
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Respiratory 288004 0
Condition category
Condition code
Respiratory 288381 288381 0 0
Other respiratory disorders / diseases

Study type
Description of intervention(s) / exposure
15 healthy subjects will be included in this study.

A 10 F catheter will be inserted into the hypopharynx via the nose. Following this the position of the tube will be confirmed using end tidal CO2 monitoring as well as a visual inspection.

Following the diagnostic setup they will be attached to the Optiflow TRADEMARK system comprising the Fisher and Paykel Healthcare MR880 humidifier delivering gas heated and humidified to 37degrees C, 44mg H2O/L. The heated circuit will comprise an RT241 circuit, an MR290 autofeed chamber and an appropriately sized adult nasal interface.

Subjects will also be assessed with EIT. For this purpose there will be a circumferential placement of a 16 electrode belt applied around the torso. The electrodes will be attached to the skin and can be removed without resulting damage or discomfort at any stage.

Participants will have pressure measurements carried out at 30, 40, 50, 60, 70, 80, 90 and 100 L/min in random order. Pressure measurement for each flow will be recorded over one minute of breathing using precision pressure transducer (PPT).
This procedure is expected to take around 60 mins. The catheter will be removed at the end of this period.

Hypopharyngeal pressure will be measured using a Honeywell precision pressure transducer (PPT – 0001 DWWW2VA-B, Honeywell International Ltd) with a laptop computer interface. The hypopharyngeal pressures will be recorded over one minute of breathing. The mean airway pressure will be determined by averaging the pressure from the peak of inspiration of the first to the last breath within the one minute recording. This will allow the entire pressure profile of each breath to be included within the mean airway pressure calculation.

Intervention code [1] 286245 0
Treatment: Devices
Comparator / control treatment
Control group

Primary outcome [1] 288552 0
To describe the relationship between flow and/or pressure delivered and mean pressure generated in the airway in a group of healthy subjects. This will be measured in the nasopharynx using a precision pressure transducer.
Timepoint [1] 288552 0
Over one minute of therapy at each given flow
Secondary outcome [1] 300452 0
To demonstrate the resulting changes in lung physiology using Electrical Impedance Tomography.
Timepoint [1] 300452 0
Over one minute while using nasal high flow

Key inclusion criteria
Healthy subjects are eligible for inclusion if all of the following criteria are met: The subject is 18 years or older; Consent has been obtained;There are no known intrathoracic pathologies known ; The subject is not on any regular medication which is known to affect the cardiopulmonary system in any way
Minimum age
18 Years
Maximum age
99 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Healthy subjects will be excluded from the study if one or more of the following criteria are present: The subject has significant nasal septum deviation; High flow nasal oxygen therapy is contraindicated.

Study design
Purpose of the study
Allocation to intervention
Non-randomised 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)
Masking / blinding
Who is / are masked / blinded?

Intervention assignment
Other design features
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment outside Australia
Country [1] 4770 0
New Zealand
State/province [1] 4770 0

Funding & Sponsors
Funding source category [1] 286498 0
Self funded/Unfunded
Name [1] 286498 0
Address [1] 286498 0
Country [1] 286498 0
Primary sponsor type
Rachael Parke
Cardiothoracic and Vascular ICU
Auckland City Hospital
Park Road
New Zealand
Secondary sponsor category [1] 285286 0
Name [1] 285286 0
Address [1] 285286 0
Country [1] 285286 0
Other collaborator category [1] 277231 0
Name [1] 277231 0
Dr Shay McGuinness
Address [1] 277231 0
Cardiothoracic and Vascular ICU
Auckland City Hospital
Park Road
Country [1] 277231 0
New Zealand

Ethics approval
Ethics application status
Ethics committee name [1] 288575 0
Central Health and Diasbility Ethics Committee
Ethics committee address [1] 288575 0
Ministry of Health
No 1 The Terrace
PO Box 5013
Ethics committee country [1] 288575 0
New Zealand
Date submitted for ethics approval [1] 288575 0
Approval date [1] 288575 0
Ethics approval number [1] 288575 0

Brief summary
High flow humidified nasal oxygen therapy (HFNOT) is a recent development that allows the provision of controlled oxygen concentrations and low levels of positive airway pressure via a nasal interface. The HFNOT system can offer clinicians and patients a different mechanism for delivering such pressure, at low levels, without some of the complications and comfort issues associated with these other methods. Some of the reported risks associated with face mask non invasive ventilation include mask discomfort, nasal dryness, oral dryness and eye irritation nasal or eye trauma and gastric distension / aspiration. Over the last three years there have been several studies published regarding the effectiveness and the clinical effect of this new form of respiratory support. Currently HFNOT is used as the standard therapy in patients with mild to moderate hypoxemic respiratory failure requiring respiratory support following extubation to improve oxygenation in patients in the Cardiothoracic and Vascular Intensive Care Unit at Auckland City Hospital. Research conducted previously by our group and others has demonstrated a positive linear correlation between the amount of flow and the resulting airway pressure with flows in the range described above. Since it is technically possible to apply higher flows with HFNOT devices we would like to describe the resulting changes in airway pressure and to see if the correlation remains linear at flows exceeding 50L/min and would like to conduct an initial study on 15 healthy volunteers.
Trial website
Trial related presentations / publications
Effect of Very-High-Flow Nasal Therapy on Airway Pressure and End-Expiratory Lung Impedance in Healthy Volunteers.

Parke RL, Bloch A, McGuinness SP.
Respir Care. 2015 Sep 1. pii: respcare.04028. [Epub ahead of print]
PMID: 26329355 [PubMed - as supplied by publisher]
Public notes

Principal investigator
Name 36738 0
Mrs Rachael Parke
Address 36738 0
Cardiothoracic and Vascular ICU
Auckland City Hospital
Park Road
Auckland 1142
Country 36738 0
New Zealand
Phone 36738 0
Fax 36738 0
Email 36738 0
Contact person for public queries
Name 36739 0
Mrs Rachael Parke
Address 36739 0
Cardiothoracic and Vascular ICU
Auckland City Hospital
Park Road
Auckland 1142
Country 36739 0
New Zealand
Phone 36739 0
Fax 36739 0
Email 36739 0
Contact person for scientific queries
Name 36740 0
Mrs Rachael Parke
Address 36740 0
Cardiothoracic and Vascular ICU
Auckland City Hospital
Park Road
Auckland 1142
Country 36740 0
New Zealand
Phone 36740 0
Fax 36740 0
Email 36740 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary