Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12617000694314
Ethics application status
Approved
Date submitted
10/05/2017
Date registered
15/05/2017
Date last updated
15/05/2017
Type of registration
Retrospectively registered

Titles & IDs
Public title
Prophylactic post-operative high flow nasal oxygen therapy versus conventional oxygen therapy in obese patients undergoing bariatric surgery: a randomised controlled pilot study
Scientific title
Prophylactic post-operative high flow nasal oxygen therapy versus conventional oxygen therapy in obese patients undergoing bariatric surgery: a randomised controlled pilot study
Secondary ID [1] 291887 0
None
Universal Trial Number (UTN)
Trial acronym
OXYBAR
High flow nasal OXYgen after BARiatric surgery
Linked study record
None

Health condition
Health condition(s) or problem(s) studied:
Obesity 303181 0
respiratory failure post surgery 303182 0
Condition category
Condition code
Respiratory 302624 302624 0 0
Other respiratory disorders / diseases
Diet and Nutrition 302672 302672 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Pre-operative management of the patient will be consistent with current surgical best practice and at the discretion of the responsible surgeon. The method and conduct of general anaesthesia will be at the discretion of the responsible anaesthetist. Given the nature of the surgery, all patients will undergo endotracheal intubation and mechanical ventilation.

Extubation will occur in theatre and all patients (control and intervention) will receive 6l of oxygen via Hudson face mask. They will then be transferred to the ICU.

Baseline measurements will be undertaken when the patient has achieved a Richmond agitation and sedation score (RASS) of -2 or greater. After baseline measurements have been recorded patients randomised to the intervention group will be managed with supplemental oxygen delivered at a FiO2 of 0.5 and a flow rate of 50 L/min via the Airvo (Trademark) 2 High Flow Nasal Oxygen device (Fisher & Paykel, New Zealand). Oxygen therapy will be titrated to maintain peripheral oxygen saturations (SpO2) =95%. This will be achieved by increasing or decreasing the FiO2 delivered. A constant flow rate of 50 L/min should be maintained for the duration of the study period. The study period will last for 6 hours following initation of HFN02.
Intervention code [1] 298002 0
Treatment: Devices
Comparator / control treatment
Pre-operative management and the conduct of general anaesthesia will be the same as that for the intervention group.

During recovery from general anaesthesia patients will be managed with supplemental oxygen delivered at 6 L/min via a Hudson mask. Oxygen therapy will be titrated to maintain peripheral oxygen saturations (SpO2) =95%. If after an initial period of stabilisation in the ICU, patients consistently achieve or exceed the SpO2 target, therapy may be titrated downwards (including the use of conventional nasal cannulae). A minimum of 2 L/min of supplemental oxygen should be maintained for the duration of the study period.
Control group
Active

Outcomes
Primary outcome [1] 302033 0
Change in end-expiratory lung impedance (EELI) as a surrogate for end-expiratory lung volume (EELV), measured by electrical impedance tomography (EIT).
Timepoint [1] 302033 0
A 2 minute continuous EIT recordings will be carried out as a baseline, with all patients receiving 6L of oxygen via Hudson face mask.
Further 2 minute EIT recordings will be carried out at 15 mins, 30 mins, 60 mins, 3 hours and 6 hours following initiation of HFN02.
Secondary outcome [1] 334574 0
Change in tidal variance as a surrogate for tidal volume, measured by EIT
Timepoint [1] 334574 0
A 2 minute continuous EIT recordings will be carried out as a baseline, with all patients receiving 6L of oxygen via Hudson face mask.
Further 2 minute EIT recordings will be carried out at 15 mins, 30 mins, 60 mins, 3 hours and 6 hours following initiation of HFN02.
Secondary outcome [2] 334652 0
Pa02:Fi02 ratio
Timepoint [2] 334652 0
Blood gas analysis will be carried out at baseline, 1 hour, 3 hours and 6 hours, post initiation of HFN02.
Secondary outcome [3] 334653 0
Change in Pac02
Timepoint [3] 334653 0
Blood gas analysis will be carried out at baseline, 1 hour, 3 hours and 6 hours post initiation of HFN02.
Secondary outcome [4] 334654 0
Incidence of post operative respiratory complications.
Timepoint [4] 334654 0
30 days post operatively
Retrospective review of medical notes.
Secondary outcome [5] 334655 0
Length of hospital stay
Timepoint [5] 334655 0
Measured in days
Secondary outcome [6] 334656 0
Patient comfort, measured by the modified Borg score
Timepoint [6] 334656 0
Measured at baseline, 1 hour, 3 hours and 6 hours after initiation of HFN02.

Eligibility
Key inclusion criteria
Age >18 yrs
BMI >32 kg/m2
Undergoing a laparoscopic bariatric procedure for weight reduction
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Age <18 yrs
Refusal of informed consent
Any contraindication to HFN02 therapy (see below)
Chest circumference too large for EIT belt (Chest > 75cm in diameter from left to right mid-axillae)

Contraindications to HFN02
Epistaxis
Significant facial trauma
Base of skull fracture
Nasal obstruction; e.g. nasal fracture, tenacious secretions, tumour

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 concealment will be maintained using sequentially numbered sealed opaque envelopes. Envelopes will be prepared by an independent person. Each envelope will contain a unique patient identifier code and will allocate the participant to either the intervention group (HFN02) or the control group (standard oxygen therapy).
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation will be achieved using a computer-generated random number table.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
The theatre team will be blinded to the allocation. Due to the research design, neither the individual collecting data nor patient can be blinded to treatment allocation.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
3/04/2017
Date of last participant enrolment
Anticipated
30/09/2017
Actual
Date of last data collection
Anticipated
31/10/2017
Actual
Sample size
Target
64
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
QLD
Recruitment hospital [1] 7979 0
St Andrew's War Memorial Hospital - Brisbane
Recruitment postcode(s) [1] 15954 0
4001 - Brisbane

Funding & Sponsors
Funding source category [1] 296383 0
Charities/Societies/Foundations
Name [1] 296383 0
Wesley Medical Research
Country [1] 296383 0
Australia
Primary sponsor type
Hospital
Name
St Andrews War Memorial Hospital
Address
547 Wickham Terrace,
Brisbane City
QLD 4001
Country
Australia
Secondary sponsor category [1] 295331 0
None
Name [1] 295331 0
Address [1] 295331 0
Country [1] 295331 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 297621 0
The UnitingCare Health Human Research Ethics Committee
Ethics committee address [1] 297621 0
Ethics committee country [1] 297621 0
Australia
Date submitted for ethics approval [1] 297621 0
03/01/2017
Approval date [1] 297621 0
21/02/2017
Ethics approval number [1] 297621 0
UCH HREC 1709

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 74618 0
Prof John Fraser
Address 74618 0
Intensive Care Unit
St Andrews War Memorial Hospital
457 Wickham Terrace,
Brisbane City
QLD 4001
Country 74618 0
Australia
Phone 74618 0
+61 7 3834 4444
Fax 74618 0
Email 74618 0
[email protected]
Contact person for public queries
Name 74619 0
Rachel Fulton
Address 74619 0
Intensive Care Unit
St Andrews War Memorial Hospital
457 Wickham Terrace,
Brisbane City
QLD 4001
Country 74619 0
Australia
Phone 74619 0
+61 7 3834 4444
Fax 74619 0
Email 74619 0
[email protected]
Contact person for scientific queries
Name 74620 0
John Fraser
Address 74620 0
Intensive Care Unit
St Andrews War Memorial Hospital
457 Wickham Terrace,
Brisbane City
QLD 4001
Country 74620 0
Australia
Phone 74620 0
+61 7 3834 4225
Fax 74620 0
Email 74620 0
[email protected]

No information has been provided regarding IPD availability


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
SourceTitleYear of PublicationDOI
EmbaseHigh flow nasal oxygen after bariatric surgery (OXYBAR), prophylactic post-operative high flow nasal oxygen versus conventional oxygen therapy in obese patients undergoing bariatric surgery: Study protocol for a randomised controlled pilot trial.2018https://dx.doi.org/10.1186/s13063-018-2777-2
EmbaseProphylactic Postoperative High Flow Nasal Oxygen Versus Conventional Oxygen Therapy in Obese Patients Undergoing Bariatric Surgery (OXYBAR Study): a Pilot Randomised Controlled Trial.2021https://dx.doi.org/10.1007/s11695-021-05644-y
N.B. These documents automatically identified may not have been verified by the study sponsor.