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Trial registered on ANZCTR


Registration number
ACTRN12612000794808
Ethics application status
Approved
Date submitted
17/05/2012
Date registered
27/07/2012
Date last updated
19/07/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
Does changing the continuous positive airways pressure (CPAP) interface alter pressure requirements in patients with obstructive sleep apnoea
Scientific title
Does changing the continuous positive airways pressure (CPAP) interface alter pressure requirements in patients with obstructive sleep apnoea?
Nasal versus full face. Same pressure?
Secondary ID [1] 279788 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obstructive sleep apnea 285666 0
Condition category
Condition code
Respiratory 285847 285847 0 0
Sleep apnoea

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients will be assigned to using an auto-titrating positive airways pressure (APAP) device overnight for 2 weeks using a nasal interface and two weeks using a full face interface. The nasal interface covers the nose only. The full face interface covers the nose and mouth. A full face interface may be used if a patient is unable to keep their mouth shut resulting in a pressure leak from the mouth. This therapy applies positive airways pressure to the upper airway and leaks result in a loss of effective pressure. As the full face mask sits lower on the face, it is postulated that adjusting the interface to seal the mask will apply pressure to the lower jaw. This may cause the jaw to be pulled back towards the airway causing the airway to narrow and thus a higher pressure may be required to maintain airway patency. The nasal interface sits above the top lip and any adjustment of this interface does not cause the jaw to move.

The first interface will be assigned in random order. This is a crossover study and there is no washout period between treatments.
Intervention code [1] 284107 0
Treatment: Devices
Comparator / control treatment
Patients will be assigned to using an auto-titrating positive airways pressure device overnight for 2 weeks using a nasal interface and two weeks using a full face interface. The first interface will be assigned in random order. This is a crossover study and there is no washout period between treatments. The nasal interface will be deemed to be the control in this study.
Control group
Active

Outcomes
Primary outcome [1] 286353 0
The primary outcome measure is required therapeutic pressure. This will be acquired from the downloaded data from the auto-titrating device which calculates the 95th centile pressure using a programmed algorithm.
Timepoint [1] 286353 0
Required therapeutic pressure is measured after 2 weeks of each interface use.
Secondary outcome [1] 295651 0
Patient's preference. This will be assessed by asking the patient which interface they prefer. They will also be given a Visual Analogue Scale at the end of each two week period to assess:
1) how comfortable was the mask
2) how well did it seal
3) how easy was it to use
They will also be asked to make any other comment about the mask.
Timepoint [1] 295651 0
Patient's preference enquired after completion of study.

Eligibility
Key inclusion criteria
Patients who have been diagnosed with obstructive sleep apnoea and who are currently using CPAP therapy and are able to tolerate both a nasal interface and a full face interface.
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Pregnant women
Intellectually or mentally impaired patients
Patients highly dependant on medical care
Patients currently experiencing other problems with CPAP that affect their use of therapy

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)
Patients who are seen in the Sleep Disorders Centre who are on CPAP therapy and are able to tolerate both a nasal interface and a full face interface will be asked to participate. Patients will have the study explained to them and given a Participant Information Sheet. If agreeable, they will then be asked to sign the Consent Form which will be kept in the Sleep Disorders Centre. Patients will be assigned to undergo two weeks treatment using a nasal interface and two weeks using a full face interface in random order. Allocation is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation by using a randomisation table created by computer software.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Random order crossover design.
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
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)
QLD

Funding & Sponsors
Funding source category [1] 285175 0
Self funded/Unfunded
Name [1] 285175 0
Address [1] 285175 0
Country [1] 285175 0
Australia
Primary sponsor type
Hospital
Name
The Princess Alexandra Hospital
Address
199 Ipswich Road
Woolloongabba
Queensland
4102
Country
Australia
Secondary sponsor category [1] 284043 0
None
Name [1] 284043 0
Address [1] 284043 0
Country [1] 284043 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 287182 0
Princess Alexandra Hospital Human Research Ethics Committee
Ethics committee address [1] 287182 0
Human Research Ethics Committee
Centres for Health Research
Princess Alexandra Hospital
199 Ipswich Road Woolloongabba
Queensland
4102
Ethics committee country [1] 287182 0
Australia
Date submitted for ethics approval [1] 287182 0
Approval date [1] 287182 0
25/11/2009
Ethics approval number [1] 287182 0
HREC/09/QPAH/244

Summary
Brief summary
Continuous positive airways pressure (CPAP) is the treatment of choice for patients who have obstructive sleep
apnoea (OSA). The patient wears an interface attached to a pump which delivers pressurized air to the upper airway,
thereby splinting the airway open. The interface is usually one of three types, nasal pillows which sit directly in the
nostrils, a nasal mask which covers the nose or a full-face mask which covers the nose and mouth. The nasal pillows
and nasal mask require the patient to keep their mouth closed during treatment as opening the mouth releases
pressure and this mouth leak results in less air pressure in the upper airway where it is required to splint the airway.
The full-face mask ensures the nose and mouth are both in the pressurised area and thus prevents mouth leak from
being a problem. Although the difference in dead space between the interfaces has been examined, the effect of the mechanical pressure from the headgear on the position of the lower jaw which is required to seal the full-face mask
has not been clearly assessed. The force applied to the headgear to seal the full-face mask may result in the lower
jaw being pushed back and thus the diameter of the upper airway being reduced. If this occurs, a higher CPAP
pressure would be required to splint the airway. An alternative treatment for OSA is the mandibular advancement splint which relies on a dental device to pull the jaw forward to enlarge the airway opening. It is not unreasonable to presume that pressure in the reverse direction would have the opposite effect. This study aims to assess the pressure requirements of nasal versus full-face mask in patients with OSA by using auto-titrating continuous positive airways pressure (APAP).The APAP devices sense flow limitation and snore and respond to these by increasing or decreasing the positive airways pressure as required. The downloaded data can be examined to assess the pressure requirements of the patient. Patients will be assessed in a random order, crossover study comprising a two week period each of a suitably fitted nasal interface and a suitably fitted full-face interface. As the data will be collected over a two week period, night to night variation should be minimised. The APAP will assess the pressure requirements for each period to examine if there is any difference in pressure requirements between the two interfaces. The Mallampati score and pharyngeal dimensions will also be evaluated to examine if this is a possible pre-disposing factor.
Trial website
Trial related presentations / publications
22nd Annual Scientific Meeting of the Australasian Sleep Association and Australasian Sleep Technologists Association, Christchurch, New Zealand, 21-23 October 2010: Poster presentation with oral component.
Public notes

Contacts
Principal investigator
Name 33674 0
Mrs Teresa Shirlaw
Address 33674 0
Sleep Disorders Centre Princess Alexandra Hospital Ipswich road Woolloongabba Queensland 4102
Country 33674 0
Australia
Phone 33674 0
+61 7 3176 5751
Fax 33674 0
Email 33674 0
teresa.shirlaw@health.qld.gov.au
Contact person for public queries
Name 16921 0
Mrs Teresa Shirlaw
Address 16921 0
Sleep Disorders Centre
Princess Alexandra Hospital
Ipswich road
Woolloongabba Queensland 4102
Country 16921 0
Australia
Phone 16921 0
+61 7 3176 5751
Fax 16921 0
+61 7 3176 7096
Email 16921 0
teresa.shirlaw@health.qld.gov.au
Contact person for scientific queries
Name 7849 0
Mrs Teresa Shirlaw
Address 7849 0
Sleep Disorders Centre
Princess Alexandra Hospital
Ipswich road
Woolloongabba Queensland 4102
Country 7849 0
Australia
Phone 7849 0
+61 7 3176 5751
Fax 7849 0
+61 7 3176 5751
Email 7849 0
teresa.shirlaw@health.qld.gov.au

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