Model-based parameter estimation using cardiovascular response to orthostatic stress

Heldt, T.; Shim, E. B.; Kamm, R. D.; Mark, R. G.

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NASA NTRS · 20040087462

Model-based parameter estimation using cardiovascular response to orthostatic stress

Heldt, T.·Shim, E. B.·Kamm, R. D.·Mark, R. G.

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Abstract

This paper presents a cardiovascular model that is capable of simulating the short-term (< or approximately equal to 3 min) transient hemodynamic response to gravitational stress and a gradient-based optimization method that allows for the automated estimation of model parameters from simulated or experimental data. We perform a sensitivity analysis of the transient heart rate response to determine which parameters of the model impact the heart rate dynamics significantly. We subsequently include only those parameters in the estimation routine that impact the transient heart rate dynamics substantially. We apply the estimation algorithm to both simulated and real data and showed that restriction to the 20 most important parameters does not impair our ability to match the data.

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Non-NASA Center NASA Program Biomedical Research and Countermeasures NASA Discipline Cardiopulmonary Heart Rate/physiology Models, Cardiovascular Computer Simulation Hemodynamic Processes/physiology Hypotension, Orthostatic/physiopathology Gravitation Human Least-Squares Analysis Cardiovascular Deconditioning/physiology Posture/physiology Support, U.S. Gov't, Non-P.H.S Sensitivity and Specificity Algorithms Normal Distribution Baroreflex/physiology Head-Down Tilt

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Heldt, T., Shim, E. B., Kamm, R. D., Mark, R. G.. 2001-01-01. Model-based parameter estimation using cardiovascular response to orthostatic stress. https://ntrs.nasa.gov/citations/20040087462

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