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.MethodsPatients 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.ResultsThe 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).ConclusionOur 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.Trial RegistrationControlled-Trials.com ISRCTN12362720; European Clinical Trials Database 2004-001866-41

Background and Purpose-Patients who have had a stroke are at risk of hypoxia through alterations in the central regulation of respiration, through aspiration, and through respiratory muscle weakness. Sleep-related breathing disorders are common and may lead to episodes of nocturnal hypoxia even when daytime oxygenation is normal. The aim of this study was to assess the prevalence of unexpected nocturnal hypoxia in stroke patients. Methods-Consecutive adult patients with stroke were recruited within 72 hours of admission to hospital. Patients with indications for oxygen treatment were excluded. Older adults from the local community were recruited as control subjects. Oxygenation was assessed by pulse oximetry (Minolta 3i) for 5 minutes when awake before bedtime and continuously from 11 PM until 7 AM. Results-Of the 238 potentially eligible stroke patients, 120 were excluded because they required oxygen, 118 were recruited, and 100 had adequate pulse oximetry data. The meanϮSD age was 74Ϯ8 years for stroke patients and 72Ϯ8 years for control subjects (nϭ85). Mean awake oxygen saturation (SO 2 ) was 94.5Ϯ1.7% for the stroke group and 95.8Ϯ1.7% for the control group (PϽ0.001). Mean nocturnal SO 2 was 93.5Ϯ1.9% in stroke patients and 94.3Ϯ1.9% in control subjects (PϽ0.01). Stroke patients had a higher oxygen desaturation index (ODI 4%) (8.9 versus 2.1, PϽ0.001).In addition, 23% of stroke patients spent Ͼ30 minutes with SO 2 Ͻ90% during the night. Conclusions-Oxygen saturation at night is Ϸ1% lower than when awake. Almost a quarter of stroke patients who are normoxic at screening during the day spend Ͼ30 minutes with an oxygen saturation Ͻ90%.

IntroductionPost-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.MethodsPatients 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.ResultsOut 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.ConclusionsNone 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.Trial RegistrationControlled-Trials.com ISRCTN12362720; Eudract.ema.europa.eu 2004-001866-41

Background: The National Institute of Health Stroke Scale (NIHSS) and the Scandinavian Stroke Scale (SSS) are commonly used in clinical stroke trials. Use of different scales in trials makes comparison of outcomes difficult. Methods: Adult patients with an acute stroke were recruited within 24 h of onset, and NIHSS, SSS and Glasgow Coma Scale scores were assessed at baseline and repeated at 1 week. Results and Conclusions: A total of 144 patients were included (46% males, mean age = 73 years). At presentation the median SSS score was 38 (2–58), and a week later 40 (4–58), the median NIHSS score at presentation was 5 (0–29) and a week later 3 (0–27). Changes in both scales were strongly correlated, r = 0.76, p < 0.001. Both were good predictors of mortality. Linear regression analysis produced an equation relating the two: SSS = 50 – 2 × NIHSS.