Condition category
Respiratory
Date applied
15/09/2008
Date assigned
11/12/2008
Last edited
30/11/2012
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims?
There is an increase worldwide in obesity and obesity related respiratory problems. In patients with severe obesity, significant breathing problems can develop which may prevent them from breathing properly during sleep. This can cause a build-up of waste gas in the blood and is called respiratory failure. Although this problem is increasingly common the best way to treat it remains unclear. The study was designed to evaluate a new medical device aimed at better controlling patients’ breathing during sleep in order to improve their breathing.

Who can participate?
Patients can participate in the study if they suffer with both severe obesity and respiratory failure without other underlying breathing or muscle problems.

What does the study involve?
The study involves being randomly picked to receive either standard treatment or the new device for a 3 month period. Patients will be unaware of which device they are given and will perform a number of tests to assess breathing and sleep as well as complete questionnaires to inform us as to how their condition affects their everyday lives.

What are the possible benefits and risks of participating?
It is not thought that there are any specific risks associated with the new device but taking part in the trial will involve additional trips to hospital. It is hoped that the new device may offer some improvements in symptom control and tolerability for patients.

Where is the study run from?
The lead study site is the Lane Fox Unit, St Thomas’ Hospital part of the King’s Academic Health Science Centre.

When is the study starting and how long is it expected to run for?
The study started in 2008 and was completed in 2010.

Who is funding the study?
Philips-Respironics

Who is the main contact?
Dr Patrick Murphy
patrickmurphy1@nhs.net

Trial website

Contact information

Type

Scientific

Primary contact

Dr Nicholas Hart

ORCID ID

Contact details

Lane Fox Respiratory Unit
St Thomas' Hospital
Department of Critical Care
Guy's and St Thomas' NHS Foundation Trust
Lambeth Palace Road
London
SE1 7EH
United Kingdom
nicholas.hart@gstt.nhs.uk

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

EAME2007AVAPS001

Study information

Scientific title

Acronym

AVAPS-OHS

Study hypothesis

Average volume-assured pressure support (AVAPS) mode will deliver nocturnal ventilatory support more effectively than the spontaneous/times (S/T) mode and have greater physiological and clinical benefits in a subgroup of obesity hypoventilation syndrome (OHS) patients with severe obesity and marked daytime hypercapnia.

Ethics approval

Guys Research Ethics Committee, South London REC Office 3 gave approval on the 21st January 2008 (ref: 07/H0804/140)

Study design

Randomised parallel-group controlled trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet

Condition

Obesity hypoventilation syndrome

Intervention

Bi-level positive airway pressure (BiPAP) ventilator will provide both the S/T and AVAPS modes.

Total duration of intervention/follow-up: 3 months

Intervention type

Other

Phase

Not Specified

Drug names

Primary outcome measures

Effectiveness of the nocturnal ventilatory support, assessed using the PaCO2 - daytime arterial blood gas (ABG) at baseline and 3 months

Secondary outcome measures

Physiological and clinical benefits in a subgroup of OHS patients with severe obesity and marked daytime hypercapnia, assessed by the following at baseline and 3 months:
1. Partial pressure of oxygen in arterial blood (PaO2), pH, bicarbonate areterial blood gas (HCO3-ABG)
2. Health related quality of life: Severe Respiratory insufficiency Questionnaire, Fatigue Severity Questionnaire
3. Anthropometric data: weight, BMI, neck, hip and waist circumference
4. Activity: Actiwatch®
5. Daytime vigilance: Epworth Sleepiness Scale, Oxford Sleep Resistance (OSLER) test

Overall trial start date

01/09/2008

Overall trial end date

01/09/2009

Reason abandoned

Eligibility

Participant inclusion criteria

1. Both males and females, aged 18 - 90 years
2. Body mass index (BMI) greater than 40 kg/m^2
3. Daytime partial pressure of carbon dioxide in the arterial blood (PaCO2) greater than 6.5 kPa

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

40

Participant exclusion criteria

Forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) less than 70%

Recruitment start date

01/09/2008

Recruitment end date

01/09/2009

Locations

Countries of recruitment

United Kingdom

Trial participating centre

Lane Fox Respiratory Unit
London
SE1 7EH
United Kingdom

Sponsor information

Organisation

Respironics International, Inc. (France)

Sponsor details

20 Rue-Jacques Daguerre
Rueil-Malmaison
Paris
92500
France
steven.coughlin@respironics.com

Sponsor type

Industry

Website

http://www.respironics.com

Funders

Funder type

Industry

Funder name

Respironics International, Inc. (France)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

1. 2012 results in http://www.ncbi.nlm.nih.gov/pubmed/22382596

Publication citations

  1. Results

    Murphy PB, Davidson C, Hind MD, Simonds A, Williams AJ, Hopkinson NS, Moxham J, Polkey M, Hart N, Volume targeted versus pressure support non-invasive ventilation in patients with super obesity and chronic respiratory failure: a randomised controlled trial., Thorax, 2012, 67, 8, 727-734, doi: 10.1136/thoraxjnl-2011-201081.

Additional files

Editorial Notes