Condition category
Respiratory
Date applied
02/01/2009
Date assigned
30/01/2009
Last edited
04/07/2011
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

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 measures

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

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

http://www.bartsandthelondon.org.uk

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

Results - basic reporting

Publication summary

1. 2010 results in http://www.ncbi.nlm.nih.gov/pubmed/20796307

Publication citations

  1. 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.

Additional files

Editorial Notes