A Randomized Controlled Trial of the Effect of Fixed-dose Routine Nocturnal Oxygen Supplementation on Oxygen Saturation in Patients with Acute Stroke
Received 18 September 2008; received in revised form 3 February 2009; accepted 11 February 2009.
Background
Mild hypoxia is common in patients with stroke, and associated with worse long-term outcome. Oxygen supplementation could prevent hypoxia and improve recovery. A previous study of routine oxygen supplementation showed no benefit after acute stroke, but did not report compliance and the effect on oxygenation. The aim of this study was to assess the effect of routine low-flow oxygen supplementation on oxygen saturation (SpO2) in patients with acute stroke.
Methods
In all, 63 patients with normoxic stroke and no indications for oxygen treatment were randomized to 2 L/min oxygen supplementation via nasal cannulae overnight or to control (room air) within 72 hours of symptom onset. Additional oxygen was given at the discretion of the clinical team, if medically indicated. SpO2 was assessed from 22:00 to 09:00 by pulse oximetry. Compliance with the trial treatment and sleep status were recorded by nursing staff.
Results
In all, 59 patients were confirmed to have had a stroke and available for overnight monitoring. Six (2 oxygen, 4 control) had no or insufficient oximetry data for analysis. The mean nocturnal SpO2 was 2.5% higher in the oxygen group (n = 27) than in the control group (n = 26) (P < .001). More patients on oxygen than control subjects had SpO2 greater than 90% throughout the night (59% v 23%). Patients on oxygen had fewer desaturations than control subjects (oxygen desaturation index 4%, 0.8 v 2.1) (P = .001). Oxygen was found to be in place as prescribed in 71%. Oxygen supplementation was not associated with insomnia or restlessness. No patient in either group was given oxygen for clinical indications.
Conclusions
Nocturnal oxygen supplementation at a rate of 2 L/min increases the mean nocturnal SpO2 by 2.5% and reduces the number of nocturnal desaturations in patients with acute stroke.
∗Stroke Research Group, Keele University, Staffordshire, United Kingdom
†Department of Respiratory Medicine, University Hospital of North Staffordshire, Staffordshire, United Kingdom
‡Institute for Life Courses Studies, Keele University, Staffordshire, United Kingdom
Address correspondence to Christine Roffe, MD, Stroke Research office, Royal Infirmary, University Hospital of North Staffordshire, Stoke-on-Trent, ST4 7LN, United Kingdom.
North Staffordshire Medical Institute funded the purchase of the pulse oximeters.
ABSTRACT