Condition category
Circulatory System
Date applied
19/06/2007
Date assigned
10/07/2007
Last edited
19/06/2014
Prospective/Retrospective
Prospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

http://www.so2s.co.uk

Contact information

Type

Scientific

Primary contact

Dr Christine Roffe

ORCID ID

Contact details

SOS STudy
Stroke Research
Medical Illustrations
Royal Infirmary
Prince's Road
Hartshill
Stoke-on-Trent
ST4 7LN
United Kingdom
+44 (0)1782 555875
Christine.roffe@northstaffs.nhs.uk

Additional identifiers

EudraCT number

2006-003479-11

ClinicalTrials.gov number

Protocol/serial number

06/Q2604/109

Study information

Scientific title

Acronym

SO2S

Study hypothesis

Main Hypothesis:
Fixed dose oxygen treatment during the first three days after an acute stroke improves outcome.

Secondary hypothesis:
Restricting oxygen supplementation to night time only is more effective than continuous supplementation.

The pilot study of this trial can be found at ISRCTN12362720 (http://www.controlled-trials.com/ISRCTN12362720).

Ethics approval

Ethics approval received from the Local Research Ethics Committee (Mellor House, Corporation Sreet, Stafford, ST16 3SR, UK) on the 31st October 2006 (ref: 06/Q260/109; EudraCT no: 2006-003479-11). Protocol version 2 approved on 24th January 2007 and on the 26th June 2008.

Study design

A multi-centre, prospective, randomised, open, blinded-endpoint study.

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Patient information can be found at http://www.so2s.co.uk/

Condition

Stroke, cerebral infarct, intracerebral haemorrhage, cerebrovascular disease

Intervention

Please note that as of 01/05/2008 the anticipated start date of this trial has been updated. The previous anticipated start date of this trial was 01/11/2007. Please also note that this trial is open to other countries. If your centre is interested in joining this trial, then please use the contact details below to discuss this matter.

Interventions:
Treatment group 1: no routine oxygen supplementation during the first 72 hours after randomisation.

Treatment group 2: oxygen per nasal cannula overnight (21:00 - 7:00) at a flow rate of 3 L/min (if baseline oxygen saturation is 93% or below) or at a flow rate of 2 L/min (if baseline oxygen saturation is greater than 93%) during the first three nights after randomisation.

Treatment group 3: oxygen per nasal cannula continuously (day and night) at a flow rate of 3 L/min (if baseline oxygen saturation is 93% or below) or a flow rate of 2 L/min (if baseline oxygen saturation is greater than 93%) during the first 72 hours after randomisation.

All patients will have regular observations of vital signs (blood pressure, heart rate, temperature and oxygen saturation) as per the local protocol of the stroke unit, but at least six-hourly. Treatment of any abnormal findings will be independent of trial allocation. Patients who require oxygen or changes in the dose of oxygen for clinical reasons at any time of the trial will be given the concentration of oxygen they require.

Sponsor email address: r&d@northstaffs.nhs.uk

Intervention type

Drug

Phase

Not Specified

Drug names

Oxygen

Primary outcome measures

Modified Rankin Scale score at three months.

Secondary outcome measures

1. Secondary outcomes at one week:
1.1. Mortality
1.2. Number of patients with neurological deterioration (death or a greater than 4 point increase in the National Institutes of Health Stroke Scale [NIHSS])
1.3. Deaths
1.4. Highest oxygen saturation during the first 72 hours
1.5. Lowest oxygen saturation during the first 72 hours

2. Secondary outcomes at three months:
2.1. Mortality
2.2. Percentage of patients living at home
2.3. Ability to perform activities of daily living (Barthel index)
2.4. Quality of life (EuroQuol)
2.5. Extended Activities of Daily Living (Nottingham EADL score)

Overall trial start date

20/04/2008

Overall trial end date

01/11/2013

Reason abandoned

Eligibility

Participant inclusion criteria

Adult patients (either sex) are eligible for trial inclusion if they were admitted with symptoms of an acute stroke within the preceding 24 hours, and if, in the doctor’s opinion, there is no clear indication for and no clear contraindication against oxygen treatment:
1. Potential indications for oxygen treatment could be:
1.1. Oxygen saturation on air less than 90%
1.2. Hypoxia associated with acute left ventricular failure
1.3. Severe pneumonia
1.4. Pulmonary embolus
1.5. Chronic respiratory failure patients treated with long term oxygen at home
2. Potential contraindications to fixed dose oxygen treatment could be:
2.1. Type 2 respiratory failure
2.2. Very severe hypoxia
3. Medical centres are eligible for participation in the study if they admit patients with acute stroke, are able to provide oxygen treatment and monitor oxygen saturation, and if there is a local researcher who will act as the principal investigator for the locality

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

6000

Participant exclusion criteria

Patients will be excluded from the trial if:
1. The responsible doctor considers the patient to have definite indications for or contraindications to oxygen treatment at a rate of 2 - 3 L/min. The decision will be left to the responsible clinician
2. The stroke is not the main clinical problem
3. He/she has another serious life-threatening illness likely to lead to death within the next few months. This group of patients is excluded because it is unlikely that they are going to derive any benefit from the trial treatment

Recruitment start date

20/04/2008

Recruitment end date

01/11/2013

Locations

Countries of recruitment

United Kingdom

Trial participating centre

SOS STudy, Stroke Research, Medical Illustrations
Stoke-on-Trent
ST4 7LN
United Kingdom

Sponsor information

Organisation

North Staffordshire Combined Healthcare NHS Trust (UK)

Sponsor details

Research & Development Department
North Staffordshire Combined Healthcare NHS Trust
Trust Headquarters
Bellringer Road
Trentham
Stoke-on-Trent
ST4 8HH
United Kingdom
+44(0)1782 441687

Sponsor type

Government

Website

http://www.nsch-tr.wmids.nhs.uk/site/show_page.php3?page_id=1

Funders

Funder type

Government

Funder name

North Staffordshire Combined Healthcare NHS Trust (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Funder name

Keele University (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Funder name

National Institute for Health Research (UK) - Research for Patient Benefit (RfPB) fund

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

2014 protocol in: http://www.ncbi.nlm.nih.gov/pubmed/24684940
2014 statistical analysis plan in: http://www.ncbi.nlm.nih.gov/pubmed/24939648

Publication citations

  1. Protocol

    Roffe C, Nevatte T, Crome P, Gray R, Sim J, Pountain S, Handy L, Handy P, The Stroke Oxygen Study (SO2S) - a multi-center, study to assess whether routine oxygen treatment in the first 72 hours after a stroke improves long-term outcome: study protocol for a randomized controlled trial., Trials, 2014, 15, 99, doi: 10.1186/1745-6215-15-99.

  2. Statistical analysis plan

    Sim J, Gray R, Nevatte T, Howman A, Ives N, Roffe C, Statistical analysis plan for the Stroke Oxygen Study (SO₂S): a multi-center randomized controlled trial to assess whether routine oxygen supplementation in the first 72 hours after a stroke improves long-term outcome., Trials, 2014, 15, 229, doi: 10.1186/1745-6215-15-229.

Additional files

Editorial Notes