Analysis of dynamic cerebral autoregulation using an ARX model based on arterial blood pressure and middle cerebral artery velocity simulation.

摘要: The study aimed to model the cerebrovascular system, using a linear ARX based on data simulated by comprehensive physiological model, and assess range of applicability parametric models. Arterial blood pressure (ABP) middle cerebral arterial flow velocity (MCAV) were measured from 11 subjects non-invasively, following step changes in ABP, thigh cuff technique. By optimising parameters associated with autoregulation, non-linear optimisation technique, showed good performance (r=0.83+/-0.14) fitting MCAV. An additional five sets ABP length 236+/-154 s acquired subject at rest. These normalised rescaled coefficients variation (CV=SD/mean) 2% 10% for comparisons. Randomly generated Gaussian noise standard deviation (SD) 1% 5% was added both physiologically MCAV (SMCAV), 'normal' 'impaired' simulate real measurement conditions. SMCAV fitted modelling, autoregulation quantified 5 recovery percentage R5% responses suggests that can be assessed computing response an appropriate order, even when is considerable.