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Trial registered on ANZCTR


Registration number
ACTRN12618001256268p
Ethics application status
Not yet submitted
Date submitted
19/07/2018
Date registered
25/07/2018
Date last updated
25/07/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
Airway oxygen concentration with high flow nasal oxygen
Scientific title
Airway oxygen concentration in patients undergoing airway surgery with high flow nasal oxygen as the primary oxygenation technique
Secondary ID [1] 295421 0
nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Hypopharyngeal surgery 308660 0
laryngotracheal surgery 308941 0
Condition category
Condition code
Anaesthesiology 307599 307599 0 0
Anaesthetics
Surgery 307840 307840 0 0
Other surgery

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
The group being observed is patients undergoing elective airway surgery with apnoeic oxygenation and high flow nasal oxygen (HFNO) as their primary oxygenation technique.
The outcome or condition we are observing is the oxygen concentration in the airway, at the surgical site.
The exposure is that delivered oxygen concentration (FiO2) will be decreased from 100% to 30% for 60 seconds.
Intervention code [1] 301727 0
Not applicable
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 306607 0
Change in airway oxygen concentration.

This will be measured using a gas sampling line placed in the airway using surgical forceps. The line delivers respiratory gases to the AS5 gas analysis module fitted to GE Aisys anaesthetic machines.
Timepoint [1] 306607 0
Airway oxygen concentration will be measured continuously for 60 seconds following the change in delivered oxygen concentration.

This will be carried out once with the tip of the gas sampling line at 1cm beyond the end of the rigid laryngoscope and once with the tip of the line 6cm beyond the end of the rigid laryngoscope.

Following these two measurements the sampling line will be removed and surgery will proceed.
Primary outcome [2] 306608 0
Rate of change of oxygen concentration (% per second).

As above, this will be measured with a gas sampling line in the airway.
Timepoint [2] 306608 0
As above, airway O2 concentration will be measured continuously for 60seconds. This will provide both an overall rate of change (average over 1 minute) and a profile of the change ie exponential vs linear.

This will be carried out with the gas sampling line at 1cm and 6cm beyond the rigid laryngoscope.
Secondary outcome [1] 348990 0
Total anaesthetic apnoeic time (minutes).

This will be recorded by stopwatch from time of rocuronium administration to whichever is sooner of 1. time first spontaneous breath is taken or 2. first positive pressure ventilation breath is administered.
Timepoint [1] 348990 0
The secondary outcome is a timepoint and will be measured in minutes + seconds.
Secondary outcome [2] 348991 0
Lowest recorded O2 saturation.

O2 saturations are measured by the GE Datex monitors in real time. Lowest O2 saturation will be recorded by the anaesthetist during the anaesthetic and will be corroborated by retrospective interrogation of monitor data.
Timepoint [2] 348991 0
Lowest recorded O2 saturation during the apnoeic period.
Secondary outcome [3] 348992 0
Change of anaesthetic technique.

If prior to completion of surgery positive pressure ventilation is undertaken at the discretion of the anaesthetist, including
- bag mask ventilation
- jet ventilation
- placement of an endotracheal tube
- placement of an laryngeal mask airway

this will be considered a change of anaesthetic technique.
Timepoint [3] 348992 0
For the duration of the surgical procedure

Eligibility
Key inclusion criteria
Patients undergoing elective hypopharyngeal or laryngotracheal surgery where apnoeic oxygenation with High Flow Nasal Oxygen (HFNO) is the chosen anaesthetic technique

Patients aged 18-75 years

Patients deemed ASA 1-3
Minimum age
18 Years
Maximum age
75 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Unable to give valid consent
BMI >35
Not otherwise suitable for HFNO technique as deemed by anaesthetist
ASA 4-5

Study design
Purpose
Natural history
Duration
Cross-sectional
Selection
Defined population
Timing
Prospective
Statistical methods / analysis
Data will be presented as mean +/- standard deviation and p values will be calculated using the unpaired student's t-test

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] 10616 0
New Zealand
State/province [1] 10616 0
Christchurch, canterbury

Funding & Sponsors
Funding source category [1] 300007 0
Hospital
Name [1] 300007 0
Christchurch Public Hospital
Address [1] 300007 0
Department of Anaesthesia
Christchurch public hospital
2 Riccarton ave
Christchurch 8011
Country [1] 300007 0
New Zealand
Primary sponsor type
Hospital
Name
Christchurch public hospital
Address
Department of Anaesthesia
2 Riccarton AVe
Christchurch 8011
Country
New Zealand
Secondary sponsor category [1] 299393 0
None
Name [1] 299393 0
n/a
Address [1] 299393 0
n/a
Country [1] 299393 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 300861 0
Health and disability ethics committee NZ
Ethics committee address [1] 300861 0
Ministry of Health
Health and Disability Ethics Committee
PO box 5013
Wellington 6140
Ethics committee country [1] 300861 0
New Zealand
Date submitted for ethics approval [1] 300861 0
15/08/2019
Approval date [1] 300861 0
Ethics approval number [1] 300861 0

Summary
Brief summary
This is an observational study looking at patients undergoing airway surgery where High Flow Nasal Oxygen (HFNO) is used for patient oxygenation during a period of sustained apnoea.

The study aims to characterise the change in oxygen (O2) concentration in the airway when O2 delivered by HFNO is decreased from 100% down to 30%

This will enable us to objectively quantify oxygen levels at the surgical site when HFNO is being used to provide sustained apnoeic oxygenation

As such it is anticipated that the study will represent a valuable contribution to patient safety by informing strategies that ensure safe and optimal surgical conditions during airway surgery in the presence of an ignition source.
Trial website
n/a
Trial related presentations / publications
nil as yet
Public notes
Attachments [1] 2898 2898 0 0

Contacts
Principal investigator
Name 85070 0
Dr Nick Abbott
Address 85070 0
Department of Anaesthesia
Christchurch Public hospital
2 Riccarton ave
Christchurch 8011
Country 85070 0
New Zealand
Phone 85070 0
+6421373527
Fax 85070 0
Email 85070 0
nicholas.abbott@cdhb.health.nz
Contact person for public queries
Name 85071 0
Dr Nick Abbott
Address 85071 0
Department of Anaesthesia
Christchurch Public hospital
2 Riccarton ave
Christchurch 8011
Country 85071 0
New Zealand
Phone 85071 0
+6421373527
Fax 85071 0
Email 85071 0
nicholas.abbott@cdhb.health.nz
Contact person for scientific queries
Name 85072 0
Dr Pippa Jerram
Address 85072 0
Department of Anaesthesia
Christchurch public hospital
2 Riccarton ave
Christchurch 8011
Country 85072 0
New Zealand
Phone 85072 0
+6421747710
Fax 85072 0
Email 85072 0
pipspin@gmail.com

No information has been provided regarding IPD availability
Summary results
No Results