Document Detail

The critical closing pressure of the cerebral circulation.
MedLine Citation:
PMID:  12900178     Owner:  NLM     Status:  MEDLINE    
The critical closing pressure (CrCP) of the cerebral circulation indicates the value of arterial blood pressure (ABP) at which cerebral blood flow (CBF) approaches zero. Measurements in animals and in humans, have shown that the CrCP is significantly greater than zero. A simple mathematical model, incorporating the effects of arterial elasticity and active wall tension, shows that CrCP can be influenced by several structural and physiological parameters, notably intracranial pressure (ICP) and active wall tension. Due to the non-linear shape of the complete ABP-CBF curve, most methods proposed for estimation of CrCP can only represent the linear range of the pressure-flow (or velocity) relationship. As a consequence, only estimates of apparent CrCP can be obtained, and these tend to be significantly higher than the true CrCP. Estimates of apparent CrCP have been shown to be influenced by arterial PCO2, ICP, cerebral autoregulation, intra-thoracic pressure, and mean ABP. There is a lack of investigation, under well-controlled conditions, to assess whether CrCP is altered in disease states. Studies of the cerebral circulation need to take CrCP into account, to obtain more accurate estimates of cerebrovascular resistance changes, and to reflect the correct dynamic relationship between instantaneous ABP and CBF.
R B Panerai
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Publication Detail:
Type:  Journal Article; Review    
Journal Detail:
Title:  Medical engineering & physics     Volume:  25     ISSN:  1350-4533     ISO Abbreviation:  Med Eng Phys     Publication Date:  2003 Oct 
Date Detail:
Created Date:  2003-08-05     Completed Date:  2004-02-20     Revised Date:  2005-11-16    
Medline Journal Info:
Nlm Unique ID:  9422753     Medline TA:  Med Eng Phys     Country:  England    
Other Details:
Languages:  eng     Pagination:  621-32     Citation Subset:  IM    
Division of Medical Physics, University of Leicester, Leicester Royal Infirmary, Leicester LE1 5WW, UK.
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MeSH Terms
Blood Flow Velocity / physiology
Blood Pressure / physiology
Brain / blood supply*,  physiology*
Cerebral Arteries / physiology*
Cerebrovascular Circulation / physiology*
Computer Simulation
Hemostasis / physiology*
Models, Cardiovascular*
Models, Neurological*
Vascular Resistance / physiology

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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