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Trial registered on ANZCTR


Registration number
ACTRN12621001080819
Ethics application status
Approved
Date submitted
16/04/2021
Date registered
16/08/2021
Date last updated
16/08/2021
Date data sharing statement initially provided
16/08/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
High-flow nasal oxygen (HFNO) vs standard oxygen therapy in patients undergoing transfemoral transcatheter aortic valve implantation (TAVI)
Scientific title
A randomised controlled trial of the effect high-flow nasal oxygen (HFNO) vs standard oxygen therapy on post-surgical oxygen partial pressure in patients undergoing transfemoral transcatheter aortic valve implantation (TAVI) under conscious sedation
Secondary ID [1] 300894 0
Nil Known
Universal Trial Number (UTN)
Trial acronym
Linked study record
The current study is a pilot study utilising the same protocol as ISRCTN 13804861, with recruitment solely in Australia.

Health condition
Health condition(s) or problem(s) studied:
Aortic valve disease
316829 0
Aortic valve stenosis 322468 0
Transfemoral transcatheter aortic valve implantation 322469 0
Condition category
Condition code
Cardiovascular 315038 315038 0 0
Diseases of the vasculature and circulation including the lymphatic system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The Treating anaesthetist will administer the following intervention:
a) High Flow Nasal Oxygen (up to 50 l/min warmed and humidified using the Optiflow delivery system) OR Standard Oxygen Therapy (2 l/min increasing to 8 l/min as required, delivered via nasal specs) commenced immediately on establishment of intravenous access (approximately at the commencement of IV sedation in the form of remifentanil)
b) duration 60-90 minutes
c) Oxygen therapy ceased at the time of transfer on to the bed prior to moving the patient to the recovery room
d) Oxygen will be administered at 50L/min via HFNO at FiO2 0.3 or 2L nasal prongs (approximately FiO2 0.3) to achieve a minimum of SpO2 94-98% for patients without respiratory comorbidities OR 88-92% or patient specific target range for those at risk of hypercapnoeic respiratory failure
e) Saturation monitoring will be a routine for all patients along with end tidal carbon dioxide

Procedure:
Once the allocated oxygen therapy has begun, patients will be sedated and the TAVI procedure will commence as per standard hospital protocol:
1. Oxygen started depending on randomisation allocation
2. Conscious sedation is started (by remifentanil intravenous infusion)
3. Regional block sited on side of TAVI procedure.
4. Transthoracic echocardiogram performed.
5. An arterial blood gas (ABG) sample is taken for analysis and repeated every 20 min or as determined according to clinical need.
6. TAVI valve implantation takes place.
7. Sedation stopped once confirmed that no bleeding from femoral artery. If surgical intervention required (e.g. due to damage to femoral artery), this can normally take place under sedation and regional block, but occasionally general anaesthetic may be required.

Follow-up:
Following the TAVI procedure patients will be transferred to the recovery area and, once the standard recovery criteria are met, then transferred to the ward. Clinical data will be recorded whilst patients are on the recovery area and ward. Patients will also be asked to verbally complete a short patient comfort questionnaire (three questions with multiple choice answers)whilst in the recovery area. Patients will be followed up until the standard discharge criteria are met and the patient can be discharged home.

Serious adverse events (SAEs):
Non-serious Adverse Events will not be recorded unless they form part of the clinical event dataset. All Serious Adverse Events (SAEs) occurring between randomisation and the end of follow-up will be reported to Papworth Clinical Trials Unit Collaboration (PTUC) within 24 hours of knowledge of the event.

Data handling:
The trial will be conducted according to Good Clinical Practice and PTUCs own standard operating procedures to ensure the monitoring and safety of trial participants and data validity. A secure, restricted-user, trial-specific database will be developed at PTUC. A member of the research team will enter the data into the database, which will only be accessible by the trial personnel.
Intervention code [1] 317215 0
Treatment: Devices
Comparator / control treatment
The treating anaesthetist will administer 2L nasal prongs (approximately FiO2 0.3) to achieve a minimum of SpO2 94-98% for patients without respiratory comorbidities OR 88-92% or patient specific target range for those at risk of hypercapnoeic respiratory failure constitutes standard therapy.
Control group
Active

Outcomes
Primary outcome [1] 323337 0
The partial pressure of oxygen dissolved in the blood (PaO2) taken from an arterial blood gas sample during the procedure
Timepoint [1] 323337 0
ABG will be taken every 20 minutes or as determined by clinical need
Secondary outcome [1] 381602 0
The number of desaturations (defined as SpO2 <93% for >10 seconds or SpO2 drop more than 5% from baseline for >10 seconds) at any time during the procedure measured by pulse oximetry.
Timepoint [1] 381602 0
Duration of the procedure.
Secondary outcome [2] 381604 0
Time spent on the Recovery ward post-procedure measured in hours as taken from medical record
Timepoint [2] 381604 0
Patients Recovery stay.
Secondary outcome [3] 381606 0
Conversion to general anaesthesia during the procedure as taken from medical record or recorded real time intraoperatively
Timepoint [3] 381606 0
This will be assessed during the procedure when the decision for conversion to GA is made by the treating doctors.
Secondary outcome [4] 381607 0
Duration of oxygen provision during and post-procedure measured in hours as taken from medical record
Timepoint [4] 381607 0
Duration of study.
Secondary outcome [5] 381609 0
Time spent in hospital measured in days at discharge as taken from medical record
Timepoint [5] 381609 0
At hospital discharge
Secondary outcome [6] 396199 0
Patient satisfaction
Timepoint [6] 396199 0
Follow up questioning regarding overall comfort level, respiratory tract dryness, stomach bloating will be assessed prior to discharge,

Eligibility
Key inclusion criteria
Inclusion Criteria
• Informed consent available;
• Adult patients (> 18 years) with signed informed consent with body mass index greater than or equal to 35 kg/m2;
• Elective TAVI procedure; and
• Patients capable of performing a walk test and spirometry
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion Criteria
• No informed consent available;
• Contraindication to HFNO such as nasal septal defect;
• Uncooperative patient; and
• Need for intubation / conversion to GA during procedure.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
- After obtaining informed consent but prior to TAVI procedure participants will be randomised to one of the two treatment groups (HFNO or standard oxygen) using a computer-generated code, accessed via a web based service. Research coordinators will inform the treating anaesthetist of the allocated group and oxygen therapy will be commenced according to which group.
- No blinding of participants/participating anaesthetists is possible due to the nature of the intervention. Staff post-procedure will be strictly blinded to treatment allocation as it could potentially influence decisions regarding hospital discharge. Outcome events will be collected by research staff blinded to group allocation.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation will be used by a randomisation table created by computer software i.e. computerised sequence generation.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



The people analysing the results/data
Intervention assignment
Parallel
Other design features
Randomised; Interventional; Design type: Prevention, Device, Active Monitoring
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
Statistical Power Calculation
From the pilot stage of this study, conducted at The Royal Papworth Hospital, we measured PaO2 before and after applying HFNO to 8 patients undergoing TAVI under remifentanil conscious sedation. We found that application of HFNO (without changing patient position or level of sedation) led to a 30% increase in PaO2, from a baseline of mean (SD) 10.1 (5.2) kPa. With an alpha of 0.05 and with 90% power, we will need to study 60 patients (30 in each group). The Australian study will not account for dropouts as there are no follow ups that the patient needs to come back to hospital for. Therefore we will need to study 60 patients only (30 in each group).

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 in Australia
Recruitment state(s)
VIC
Recruitment hospital [1] 16181 0
The Alfred - Melbourne
Recruitment postcode(s) [1] 29724 0
3004 - Melbourne

Funding & Sponsors
Funding source category [1] 305345 0
Hospital
Name [1] 305345 0
The Alfred
Country [1] 305345 0
Australia
Funding source category [2] 305346 0
Commercial sector/Industry
Name [2] 305346 0
Fisher and Paykel Healthcare Limited
Country [2] 305346 0
Australia
Primary sponsor type
Hospital
Name
The Alfred
Address
55 Commercial Road, Melbourne. VIC 3004
Country
Australia
Secondary sponsor category [1] 305715 0
None
Name [1] 305715 0
Address [1] 305715 0
Country [1] 305715 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 305678 0
The Alfred Ethics Committee
Ethics committee address [1] 305678 0
55 Commercial Rd, Melbourne VIC 3004
Ethics committee country [1] 305678 0
Australia
Date submitted for ethics approval [1] 305678 0
19/03/2020
Approval date [1] 305678 0
06/05/2021
Ethics approval number [1] 305678 0
HREC/60513/Alfred-2020

Summary
Brief summary
This is a study of two different methods of providing oxygen to patients having a transcatheter aortic valve implantation (TAVI) under conscious sedation. TAVI is a type of treatment for patients who have a narrowing of the aortic valve in the heart (aortic stenosis). Traditionally treatment of aortic stenosis has required open-heart surgery but with this procedure doctors can place a new valve in the heart through one of the large blood vessels in the leg (transfemoral TAVI). Usually patients having a TAVI recover from their treatment faster and can go home sooner. Also, unlike patients having open-heart surgery, patients having a TAVI will be under conscious sedation, meaning they will have been given medication to make them relaxed and sleepy but will be awake.

Sometimes during a TAVI the patient’s blood oxygen levels can become too low (known as hypoxaemia). Therefore all patients having a TAVI under conscious sedation need to be given oxygen. This study is investigating two different methods of providing oxygen to patients having a TAVI under conscious sedation. These are:
Standard oxygen therapy: via nasal cannula (tube) at low flows in the nose vs High Flow Nasal Oxygen (HFNO) at much faster rates of delivery.

The two devices are compared to see if either is better at preventing hypoxaemia (low oxygen levels in the blood) as well as improved patient comfort, a decreased need to go to a high dependency unit after the procedure and a reduced risk of changing to a general anaesthetic during the procedure.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 101198 0
Dr Stuart Hastings
Address 101198 0
The Alfred Hospital
55 Commercial Rd, Melbourne VIC 3004
Country 101198 0
Australia
Phone 101198 0
+61390763176
Fax 101198 0
Email 101198 0
Contact person for public queries
Name 101199 0
Ms Sophie Wallace
Address 101199 0
The Alfred hospital
55 Commercial Rd, Melbourne VIC 3004
Country 101199 0
Australia
Phone 101199 0
+61419372570
Fax 101199 0
Email 101199 0
Contact person for scientific queries
Name 101200 0
Ms Sophie Wallace
Address 101200 0
The Alfred Hospital
55 Commercial Rd, Melbourne VIC 3004
Country 101200 0
Australia
Phone 101200 0
+61390763176
Fax 101200 0
Email 101200 0

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?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
7469Study protocol  [email protected]
12884Informed consent form  [email protected] This is the participant information consent form t... [More Details] 379535-(Uploaded-16-08-2021-10-28-35)-Study-related document.pdf



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.