title: The SOS pilot study: a RCT of routine oxygen supplementation early after acute stroke--effect on recovery of neurological function at one week.
abstract: Mild hypoxia is common after stroke and associated with poor long-term outcome. Oxygen supplementation could prevent hypoxia and improve recovery. A previous study of routine oxygen supplementation showed no significant benefit at 7 and 12 months. This pilot study reports the effects of routine oxygen supplementation for 72 hours on oxygen saturation and neurological outcomes at 1 week after a stroke.
  
  
  METHODS
  Patients with a clinical diagnosis of acute stroke were recruited within 24 h of hospital admission between October 2004 and April 2008. Participants were randomized to oxygen via nasal cannulae (72 h) or control (room air, oxygen given only if clinically indicated). Clinical outcomes were assessed by research team members at 1 week. Baseline data for oxygen (n = 148) and control (n = 141) did not differ between groups.
  
  
  RESULTS
  The median (interquartile range) National Institutes of Health Stroke Scale (NIHSS) score for the groups at baseline was 6 (7) and 5 (7) respectively. The median Nocturnal Oxygen Saturation during treatment was 1.4% (0.3) higher in the oxygen than in the control group (p<0.001) during the intervention. At 1 week, the median NIHSS score had reduced by 2 (3) in the oxygen and by 1 (2) in the control group. 31% of participants in the oxygen group and 14% in the control group had an improvement of ≥4 NIHSS points at 1 week doubling the odds of improvement in the oxygen group (OR: 2.9).
  
  
  CONCLUSIONS
  Our data show that routine oxygen supplementation started within 24 hours of hospital admission with acute stroke led to a small, but statistically significant, improvement in neurological recovery at 1 week. However, the difference in NIHSS improvement may be due to baseline imbalance in stroke severity between the two groups and needs to be confirmed in a larger study and linked to longer-term clinical outcome.
  
  
  BACKGROUND
  Controlled-Trials.com ISRCTN12362720; European Clinical Trials Database 2004-001866-41.
authors.affiliation: Stoke Stroke Research Group, North Staffordshire Combined Healthcare Trust, Stoke-On-Trent, Staffordshire, United Kingdom. christine.roffe@northstaffs.nhs.uk
authors.forename: Christine
authors.initials: C
authors.lastname: Roffe
authors.forename: Khalid
authors.initials: K
authors.lastname: Ali
authors.forename: Anushka
authors.initials: A
authors.lastname: Warusevitane
authors.forename: Sheila
authors.initials: S
authors.lastname: Sills
authors.forename: Sarah
authors.initials: S
authors.lastname: Pountain
authors.forename: Martin
authors.initials: M
authors.lastname: Allen
authors.forename: John
authors.initials: J
authors.lastname: Hodsoll
authors.forename: Frank
authors.initials: F
authors.lastname: Lally
authors.forename: Peter
authors.initials: P
authors.lastname: Jones
authors.forename: Peter
authors.initials: P
authors.lastname: Crome
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D006760:Hospitalization; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D008297:Male; D009424:Nervous System Physiological Phenomena; D010092:Oximetry; D010100:Oxygen / Q000097:blood*; D010102:Oxygen Inhalation Therapy; D010865:Pilot Projects; D020127:Recovery of Function; D016037:Single-Blind Method; D020521:Stroke / Q000097:blood / Q000150:complications / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D010100:Oxygen