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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
High Flow Nasal Oxygen during Endobronchial Ultrasound to prevent low oxygen levels.
Scientific title
High flow humidified nasal oxygen to prevent desaturation during EBUS – a randomised controlled trial
Secondary ID [1] 289347 0
Universal Trial Number (UTN)
Trial acronym
TED: THRIVE during EBUS to prevent Desaturation
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Endobronchial Ultrasound 298972 0
Condition category
Condition code
Anaesthesiology 299037 299037 0 0
Respiratory 299038 299038 0 0
Other respiratory disorders / diseases

Study type
Description of intervention(s) / exposure
High flow humidified nasal oxygen. Oxygen administered via the Optiflow THRIVE device, at a flow rate of 50-70LPM as tolerated, humidified using the Fisher and Paykel 850 humidifier, to a humidity of 70% relative humidity. The oxygen concentration delivered from the device will be 100%, but the actual inspired oxygen concentration will vary with the patient's inspiratory flow rate and degree of air entrainment.

In the intervention group, patients will be put on a THRIVE device with oxygen delivering at 30 L/min immediately upon entering the room, but before sedation administration, for a minimum of 3 minutes. The oxygen delivering rate will be increased to 50 L/min via the THRIVE device immediately after sedation agent is given and will be maintained at 50 L/min during the procedure. The flow rate can be increased up to 70L/min if necessary by the anaesthetist or decreased to 30L/min if patient is not tolerating the device.

The EBUS procedure will only commence once a clinically appropriate level of sedation is reached, titrated by the anaesthetist. As such, oxygen administration will have occurred for a minimum of 3-5minutes before the procedure begins.

Oxygen delivery will continue until the conclusion of the EBUS procedure, and will be removed when the patient is stable for transfer to the recovery room, as judged by the anaesthetist.
Intervention code [1] 294923 0
Treatment: Devices
Comparator / control treatment
Standard oxygen therapy. Oxygen administered at 15LPM via a gutter mask.
Control group

Primary outcome [1] 298501 0
Proportion of patients experiencing desaturation (SpO2 below 90%) as measured by pulse oximetry.
Timepoint [1] 298501 0
SpO2 will be monitored continuously during anaesthesia for EBUS. Any SpO2 reading lower than 90% will be counted as an event.
Secondary outcome [1] 324405 0
SpO2 after pre-oxygenation before sedation is given as measured by pulse oximetry
Timepoint [1] 324405 0
Immediately following pre-oxygenation (approximately three minutes following start of procedure).
Secondary outcome [2] 329904 0
Number of hypoxic episodes (SpO2 below 90%) during the procedure as measured by pulse oximetry.
Timepoint [2] 329904 0
SpO2 will be monitored continuously during procedure.
Secondary outcome [3] 329905 0
Duration of hypoxia (SpO2 below 90%) in seconds during the procedure as measured by pulse oximetry.
Timepoint [3] 329905 0
SpO2 will be monitored continuously during the procedure.
Secondary outcome [4] 329906 0
Lowest SpO2 during procedure as assessed by pulse oximetry
Timepoint [4] 329906 0
SpO2 will be monitored continuously during the procedure.
Secondary outcome [5] 329907 0
End-procedure end-tidal CO2 in mmHg sampled via a catheter through the working channel of the bronchoscope and analysed via a standard infra-red gas analyser on the anaesthetic machine.
Timepoint [5] 329907 0
At conclusion of EBUS procedure
Secondary outcome [6] 329908 0
Number of interruptions to procedure to allow anaesthetic management, such as bag-mask ventilation, insertion of an LMA, intubation or other rescue airway procedure.
Timepoint [6] 329908 0
Monitored continuously during procedure.
Secondary outcome [7] 329909 0
Total time for procedure in seconds as timed with a timing watch.
Timepoint [7] 329909 0
Determined at conclusion of procedure
Secondary outcome [8] 329910 0
Patient satisfaction score as assessed with a Likert scale (0-5).
Timepoint [8] 329910 0
Once patient has recovered from anaesthesia
Secondary outcome [9] 329911 0
Proceduralist satisfaction score as reported using a Likert scale (0-5)
Timepoint [9] 329911 0
At conclusion of procedure
Secondary outcome [10] 329912 0
Anaesthetists satisfaction score as reported using a Likert scale (0-5)
Timepoint [10] 329912 0
At conclusion of procedure
Secondary outcome [11] 329913 0
Any other complications, such as arrhythmia, myocardial ischaemia and cardiac arrest as identified by the treating anaesthetist.
Timepoint [11] 329913 0
Any complication occurring during procedure.
Secondary outcome [12] 329914 0
Maximum oxygen delivering rate (L/min) as selected on the oxygen flow-meter.
Timepoint [12] 329914 0
Monitored continuously during procedure
Secondary outcome [13] 329915 0
Minimum oxygen delivering rate (L/min) as selected on the oxygen flow-meter.
Timepoint [13] 329915 0
Monitored continuously during procedure

Key inclusion criteria
Inclusion criteria will be all of:
- Adults aged greater than or equal to 18 years
- Able to give informed consent
- Planned for endobronchial ultrasound and
- Planned for sedation for their endobronchial ultrasound
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
1. Unable to give informed consent
2. Intubated, or planned for intubation or general anaesthesia for their endobronchial ultrasound
3. Pregnant patients
4. Patients with active nasal bleeding or base of skull fracture
5. Non-english speaking patients

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation concealed by central computer-generated randomisation prior to therapy initiation but after eligibility screening.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer - generated.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Phase 4
Type of endpoint(s)
Statistical methods / analysis
Fisher-exact test or Chi-square test will be used for non-parametric data. Unpaired two-tailed t-test or Mann Whitney U-test will be used for parametric data. Confidence intervals around incidence of desaturation, and the effect size will be calculated.

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 hospital [1] 5879 0
Royal Melbourne Hospital - City campus - Parkville
Recruitment postcode(s) [1] 13324 0
3050 - Royal Melbourne Hospital

Funding & Sponsors
Funding source category [1] 293726 0
Name [1] 293726 0
Royal Melbourne Hospital
Address [1] 293726 0
Grattan St,
Country [1] 293726 0
Primary sponsor type
Royal Melbourne Hospital
Grattan St,
Secondary sponsor category [1] 292558 0
Name [1] 292558 0
Address [1] 292558 0
Country [1] 292558 0

Ethics approval
Ethics application status
Ethics committee name [1] 295160 0
Melbourne Health HREC
Ethics committee address [1] 295160 0
Grattan St,
Ethics committee country [1] 295160 0
Date submitted for ethics approval [1] 295160 0
Approval date [1] 295160 0
Ethics approval number [1] 295160 0

Brief summary
Endobronchial ultrasound (EBUS) is a procedure performed to extract tissue from the lung to aid diagnosis of lung cancer, infections and sarcoidosis. To tolerate this procedure, which involves a camera on a tube being inserted into the lung, patients require sedation. The sedative medications commonly cause patients to hypoventilate, and a reduction in oxygen saturation and increase in carbon dioxide level is commonly seen, necessitating the interruption of the procedure, and occasionally putting patient’s lives at risk. An intervention to reduce the rates of these problems may make the procedure safer.

The OptiFlow THRIVE device delivers high flow oxygen via the nose, and may reduce the rate of desaturation and limit the rate of increase in CO2 level. The device has been trialed in anaesthesia in morbid obesity surgery, difficult airways in ENT and during awake fibreoptic intubation, which is a conceptually similar procedure to EBUS. The device has been used safely for many years to assist intubation in the emergency department and intensive care unit. There is no data currently using the device during EUBS, or any endoscopic procedure for that matter.

This study will randomize participants to either oxygen therapy during sedation with standard care (being a gutter mask) or OptiFlow THRIVE. The research question is: In adults undergoing endobronchial ultrasound, does oxygen therapy provided using the OptiFlow THRIVE device reduce the frequency of desaturation and hypercarbia compared to standard oxygen therapy using a gutter mask?
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 65930 0
Dr Irene Ng
Address 65930 0
Department of Anaesthesia and Pain Management
Grattan St
Country 65930 0
Phone 65930 0
Fax 65930 0
Email 65930 0
Contact person for public queries
Name 65931 0
Dr Ned Douglas
Address 65931 0
Department of Anaesthesia and Pain Management
Grattan St
Country 65931 0
Phone 65931 0
Fax 65931 0
Email 65931 0
Contact person for scientific queries
Name 65932 0
Dr Irene Ng
Address 65932 0
Department of Anaesthesia and Pain Management
Grattan St
Country 65932 0
Phone 65932 0
Fax 65932 0
Email 65932 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