Cerebrovascular pressure reactivity is related to global cerebral oxygen metabolism after head injury.

Details

Serval ID
serval:BIB_572EBB57B20C
Type
Article: article from journal or magazin.
Collection
Publications
Title
Cerebrovascular pressure reactivity is related to global cerebral oxygen metabolism after head injury.
Journal
Journal of Neurology, Neurosurgery, and Psychiatry
Author(s)
Steiner L.A., Coles J.P., Czosnyka M., Minhas P.S., Fryer T.D., Aigbirhio F.I., Clark J.C., Smielewski P., Chatfield D.A., Donovan T., Pickard J.D., Menon D.K.
ISSN
0022-3050
Publication state
Published
Issued date
2003
Peer-reviewed
Oui
Volume
74
Number
6
Pages
765-770
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Abstract
BACKGROUND: After head injury, impaired cerebrovascular autoregulation has been associated with abnormally high or low cerebral blood flow. The physiological relevance of cerebral blood flow levels is difficult to assess in these patients, whose cerebral metabolic rate for oxygen (CMRO(2)) is known to be abnormal. Investigation of these relations requires quantitative measures of cerebral blood flow and CMRO(2), to allow assessment of oxygen supply and demand relations. OBJECTIVES: To investigate the relation between dysautoregulation and global cerebral oxygen metabolism following head injury. METHODS: Using positron emission tomography, global cerebral blood flow, CMRO(2), and oxygen extraction fraction were determined in 22 patients who were investigated in 26 examinations on days 1 to 11 (mean (SD), 3.5 (2.3)) after head injury. Cerebrovascular pressure reactivity was assessed using a pressure reactivity index, calculated as the moving linear correlation coefficient between mean arterial blood pressure and intracranial pressure. Outcome was assessed six months after injury using the Glasgow outcome scale. RESULTS: Low CMRO(2) was associated with disturbed pressure reactivity (inverse function, R(2) = 0.21, p = 0.018) and there was a correlation between disturbed pressure reactivity and oxygen extraction fraction (quadratic function, R(2) = 0.55, p = 0.0001). There was no significant relation between pressure reactivity and cerebral blood flow. An unfavourable outcome was associated with disturbed pressure reactivity. There was no significant relation between outcome and CMRO(2) or oxygen extraction fraction. CONCLUSIONS: There is a close relation between dysautoregulation and abnormal cerebral metabolism but not blood flow. Further studies are needed to determine whether metabolic dysfunction is a result of or a cause of disturbed pressure reactivity, and to establish if there is a relation between cerebral oxygen metabolism and outcome.
Keywords
Adolescent, Adult, Brain/blood supply, Brain Injuries/diagnosis, Brain Injuries/metabolism, Female, Glasgow Coma Scale, Homeostasis/physiology, Humans, Intracranial Pressure/physiology, Male, Middle Aged, Oxygen/metabolism, Tomography, Emission-Computed
Pubmed
Web of science
Open Access
Yes
Create date
29/12/2009 17:07
Last modification date
20/08/2019 14:11
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