Lack of hemispheric dominance for consciousness in acute ischaemic stroke
- B Cucchiara1,
- S E Kasner1,
- D A Wolk2,
- P D Lyden3,
- V A Knappertz4,
- T Ashwood5,
- T Odergren7,
- A Nordlund6,
- For The Class-I Investigators
- 1Department of Neurology, University of Pennsylvania Medical Center, Philadelphia, USA
- 2Brigham and Women’s Hospital, Division of Cognitive and Behavioral Neurology, Boston, Massachusetts, USA
- 3Department of Neurology, University of California-San Diego, San Diego, California, USA
- 4Specialized Therapeutics, Montville, New Jersey, USA
- 5AstraZeneca Pharmaceuticals, Södertälje, Sweden
- 6Centre for Work and Rehabilitation, Faculty of Health, Linköping University, Linköping, Sweden
- 7AstraZeneca Pharmaceuticals, Wilmington, Delaware, USA
- Correspondence to: Dr Brett Cucchiara, Department of Neurology, University of Pennsylvania Medical Center, 3400 Spruce Street, Philadelphia, PA 19104, USA; cucchiar{at}mail.med.upenn.edu
- Received 25 November 2002
- Accepted 14 March 2003
- Revised 13 March 2003
Abstract
Background: Previous reports have suggested left hemispheric dominance for maintaining consciousness, although there is controversy over this claim.
Objective: To compare early impairment of level of consciousness between patients with right and left hemispheric stroke.
Methods: Data from 564 patients with ischaemic stroke enrolled in the placebo arm of a trial of a putative neuroprotectant were analysed. All patients had major hemispheric stroke with cortical dysfunction, visual field deficit, and limb weakness, with symptom onset within 12 hours of enrolment. Patients were prospectively evaluated on a predefined scale (1–6; 1 = fully awake, higher scores representing greater impairment) to measure level of consciousness at multiple time points over the initial 24 hours after presentation. The National Institutes of Health (NIH) stroke scale score at presentation and infarct volume at 30 days were determined.
Results: Some degree of impairment in level of consciousness was observed in 409 of the 564 patients (73%). Median maximum sedation score was 2 for both right and left hemispheric stroke (p = 0.91). Mean sedation score over 24 hours was 1.5 for both right and left stroke (p = 0.75). There was no difference between level of consciousness scores in right and left stroke at any individual time point during the 24 hour monitoring period. No association between side and impairment in level of consciousness was seen after adjustment for stroke severity and infarct volume.
Conclusions: In contrast to previous reports, there was no evidence for hemispheric dominance for consciousness in the setting of a major hemispheric stroke.
