Time constant of the cerebral arterial bed in normal subjects.

Détails

ID Serval
serval:BIB_83F1C611B949
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Time constant of the cerebral arterial bed in normal subjects.
Périodique
Ultrasound in Medicine and Biology
Auteur(s)
Kasprowicz M., Diedler J., Reinhard M., Carrera E., Steiner L.A., Smielewski P., Budohoski K.P., Haubrich C., Pickard J.D., Czosnyka M.
ISSN
1879-291X (Electronic)
ISSN-L
0301-5629
Statut éditorial
Publié
Date de publication
2012
Volume
38
Numéro
7
Pages
1129-1137
Langue
anglais
Notes
Publication types: Journal ArticlePublication Status: ppublish
Résumé
The time constant of cerebral arterial bed (in brief time constant) is a product of brain arterial compliance (C(a)) and resistance (CVR). We tested the hypothesis that in normal subjects, changes in end-tidal CO(2) (EtCO(2)) affect the value of the time constant. C(a) and CVR were estimated using mathematical transformations of arterial pressure (ABP) and transcranial Doppler (TCD) cerebral blood flow velocity waveforms. Responses of the time constant to controlled changes in EtCO(2) were compared in 34 young volunteers. Hypercapnia shortened the time constant (0.22 s [0.17, 0.26] vs. 0.16 s [0.13, 0.20]; p = 0.000001), while hypocapnia lengthened the time constant (0.22 s [0.17, 0.26] vs. 0.23 s [0.19, 0.32]; p < 0.0032). The time constant was negatively correlated with changes in EtCO(2) (R(partial) = -0.68, p < 0.000001). This was associated with a decrease in CVR when EtCO(2) increased (R(partial) = -0.80, p < 0.000001) and C(a) remained independent of changes in EtCO(2). C(a) was negatively correlated with mean ABP (R(partial) = -0.68, p < 0.000001). In summary, the time constant shortens with increasing EtCO(2). Its potential role in cerebrovascular investigations needs further studies.
Pubmed
Web of science
Création de la notice
05/07/2012 19:00
Dernière modification de la notice
03/03/2018 18:53
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