title: The stroke oxygen pilot study: a randomized controlled trial of the effects of routine oxygen supplementation early after acute stroke--effect on key outcomes at six months.
abstract: BACKGROUND
  Post-stroke hypoxia is common, and may adversely affect outcome. We have recently shown that oxygen supplementation may improve early neurological recovery. Here, we report the six-month outcomes of this pilot study.
  
  
  METHODS
  Patients with a clinical diagnosis of acute stroke were randomized within 24 h of admission to oxygen supplementation at 2 or 3 L/min for 72 h or to control treatment (room air). Outcomes (see below) were assessed by postal questionnaire at 6 months. Analysis was by intention-to-treat, and statistical significance was set at p ≤ 0.05.
  
  
  RESULTS
  Out of 301 patients randomized two refused/withdrew consent and 289 (148 in the oxygen and 141 in the control group) were included in the analysis: males 44%, 51%; mean (SD) age 73 (12), 71 (12); median (IQR) National Institutes of Health Stroke Scale score 6 (3, 10), 5 (3, 10) for the two groups respectively. At six months 22 (15%) patients in the oxygen group and 20 (14%) in the control group had died; mean survival in both groups was 162 days (p = 0.99). Median (IQR) scores for the primary outcome, the modified Rankin Scale, were 3 (1, 5) and 3 (1, 4) for the oxygen and control groups respectively. The covariate-adjusted odds ratio was 1.04 (95% CI 0.67, 1.60), indicating that the odds of a lower (i.e. better) score were non-significantly higher in the oxygen group (p = 0.86). The mean differences in the ability to perform basic (Barthel Index) and extended activities of daily living (NEADL), and quality of life (EuroQol) were also non-significant.
  
  
  CONCLUSIONS
  None of the key outcomes differed at 6 months between the groups. Although not statistically significant and generally of small magnitude, the effects were predominantly in favour of the oxygen group; a larger trial, powered to show differences in longer-term functional outcomes, is now on-going.
  
  
  BACKGROUND
  Controlled-Trials.com ISRCTN12362720; Eudract.ema.europa.eu 2004-001866-41.
authors.affiliation: Academic Department of Geriatrics, Brighton and Sussex Medical School, Brighton, United Kingdom.
authors.forename: Khalid
authors.initials: K
authors.lastname: Ali
authors.forename: Anushka
authors.initials: A
authors.lastname: Warusevitane
authors.forename: Frank
authors.initials: F
authors.lastname: Lally
authors.forename: Julius
authors.initials: J
authors.lastname: Sim
authors.forename: Sheila
authors.initials: S
authors.lastname: Sills
authors.forename: Sarah
authors.initials: S
authors.lastname: Pountain
authors.forename: Tracy
authors.initials: T
authors.lastname: Nevatte
authors.forename: Martin
authors.initials: M
authors.lastname: Allen
authors.forename: Christine
authors.initials: C
authors.lastname: Roffe
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory; D010100:Oxygen / Q000627:therapeutic use*; D010865:Pilot Projects; D011788:Quality of Life; D020521:Stroke / Q000188:drug therapy* / Q000503:physiopathology; D011795:Surveys and Questionnaires; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D010100:Oxygen