Contact information
Type
Scientific
Primary contact
Dr Gordon Flynn
ORCID ID
Contact details
Intensive Care Unit
Prince of Wales Hospital
Sydney
2031
Australia
docgordonflynn@yahoo.co.uk
Additional identifiers
EudraCT number
2005-003612-30
ClinicalTrials.gov number
Protocol/serial number
REC ref: 05/Q0605/150
Study information
Scientific title
A comparison of a helium-oxygen mixture (Heliox) with an oxygen air mixture in reducing the work of breathing during weaning from mechanical ventilation
Acronym
Study hypothesis
There is evidence in patients with chronic obstructive pulmonary disease (COPD) that around the period of extubation helium-oxygen leads to a reduction in the work of breathing. In a small physiological study in patients without airways disease, breathing helium-oxygen during weaning decreased the work of breathing. If so, could there be a use for helium in the weaning of patients from mechanical ventilation?
Ethics approval
East London & The City HA Local Research Ethics Committee 3, approved on 09/11/2005 (ref: 05/Q0605/150)
Study design
Prospective randomised controlled cross-over single-centre trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Hospitals
Trial type
Other
Patient information sheet
Condition
Work of breathing during weaning from mechanical ventilation
Intervention
This is a single-centre trial carried out at The Royal London Hospital.
Intervention: Helium inhaled at a concentration no less than 60%.
Patients received 2 hours of continuous positive airway pressure (CPAP) ventilation (positive end-expiratory pressure [PEEP] setting remained unchanged and pressure support set to zero) with helium-oxygen or air-oxygen via an eVent ventilator. This ventilator was calibrated for the helium oxygen mixture on an individual patient basis. Patients were returned to their pre-study ventilator settings for 2 hours, before being given the alternative gas mixture for 2 hours.
The level of CPAP support and FiO2 were unchanged for individual patients throughout the trial period.
Intervention type
Other
Phase
Phase IV
Drug names
Primary outcome measure
Work of breathing measured by carbon dioxide production.
Measurements were taken continuously but presented before starting CPAP and helium then 1 hour later then at 2 hours, patient then returned to pre-CPAP ventilator settings for 2 hours then back on CPAP with alternate gas mixture with readings taken continuously but presented at 1 and 2 hours.
Secondary outcome measures
1. Respiratory rate
2. Pulse oximetry (SpO2)
3. Alveolar minute ventilation
4. Alveolar tidal volume
5. CO2 production
6. End tidal CO2
7. Alveolar dead space (Vd/Vt)
Above measurements were taken continuously but presented before starting CPAP and helium then 1 hour later then at 2 hours, patient then returned to pre-CPAP ventilator settings for 2 hours then back on CPAP with alternate gas mixture with readings taken continuously but presented at 1 and 2 hours.
Overall trial start date
01/01/2006
Overall trial end date
01/01/2008
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. General adult intensive care unit (ICU) patients
2. Both males and females, aged between 18 and 80
3. The underlying cause of respiratory failure was improving
4. Pressure support ventilation of less than 10 cm H2O
5. No continuous intravenous sedation or inotropes
6. FiO2 less than or equal to 0.4 and requiring less than 10 cm H2O positive end expiratory pressure
7. Written informed consent from the patient or assent from their next of kin was obtained
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
24
Participant exclusion criteria
1. Failure to meet inclusion criteria
2. Inadequate analgesia
3. Pregnancy
4. Participation in other intervention trials in the past 30 days
5. Refusal of consent from the patient or assent from the next of kin
Recruitment start date
01/01/2006
Recruitment end date
01/01/2008
Locations
Countries of recruitment
United Kingdom
Trial participating centre
Intensive Care Unit
Sydney
2031
Australia
Sponsor information
Organisation
Barts and The London NHS Trust (UK)
Sponsor details
c/o Gerry Leonard
Research and Development Department
Third Floor Rutland House
42-46 New Road
Whitechapel
London
E1 2AX
United Kingdom
Sponsor type
Government
Website
Funders
Funder type
Government
Funder name
Barts and the London NHS Trust (UK)
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
Basic results (scientific)
Publication list
1. 2010 results in http://www.ncbi.nlm.nih.gov/pubmed/20796307
Publication citations
-
Results
Flynn G, Mandersloot G, Healy M, Saville M, McAuley DF, Helium-oxygen reduces the production of carbon dioxide during weaning from mechanical ventilation., Respir. Res., 2010, 11, 117, doi: 10.1186/1465-9921-11-117.