title: Assessment of dynamic changes in cerebral autoregulation.
abstract: Cerebral autoregulation (CA) is a control mechanism that adjusts cerebral vasomotor tone in response to changes in arterial blood pressure (ABP) to ensure a nearly constant cerebral blood flow. Patient treatment could be optimized if CA monitoring were possible. Whereas the concept of static CA assessment is simply based on comparison of mean values obtained from two stationary states (e.g., before and after a pressure change), the evaluation of dynamic CA is more complex. Among other methods, moving cross-correlation analysis of slow waves in ABP and cerebral blood flow velocity (CBFV) seems to be appropriate to monitor CA quasi-continuously. The calculation of an "instantaneous transfer function" between ABP and CBFV oscillations in the low-frequency band using the Wigner-Ville distribution may represent an acceptable compromise in time-frequency resolution for continuous CA monitoring.
authors.affiliation: Institute of Biomedical Engineering, Dresden University of Technology, Dresden, Germany. frank.noack@mailbox.tu-dresden.de
authors.forename: Frank
authors.initials: F
authors.lastname: Noack
authors.forename: Melanie
authors.initials: M
authors.lastname: Christ
authors.forename: Sven-Axel
authors.initials: SA
authors.lastname: May
authors.forename: Ralf
authors.initials: R
authors.lastname: Steinmeier
authors.forename: Ute
authors.initials: U
authors.lastname: Morgenstern
mesh_terms: D000465:Algorithms; D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D001921:Brain / Q000098:blood supply* / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003198:Computer Simulation; D006487:Hemostasis / Q000502:physiology*; D006801:Humans; D008955:Models, Cardiovascular; D008959:Models, Neurological