Dynamic Models and Parameter Estimation: The Hypoxic Ventilatory Response

  • Denham S. Ward

Abstract

Mathematical models of the control of breathing during dynamic changes in various stimuli (e.g., CO2, O2 and exercise) have been extremely useful [2] in understanding how ventilation is adjusted. In the physical sciences models can often be derived from fundamental physical relationships (e.g., the equations of motion for satellite orbits) but in physiology there are few such relationships to guide the model builder. The building of a model can be divided into two stages. First the structure of the model must be determined. The structure consists of the mathematical equations and any parameters that are not estimated from an individual data set (assumed values and known constants). Secondly, experiments and parameter estimation techniques are used to determine the values of certain parameters from individual experiments. The validation of the model using different data sets and experimental conditions can then be done. Frequently this validation process will suggest modifications to the model and the process starts over. This paper will discuss how some of the assumptions that must go into devising a model for the hypoxic ventilatory response determine the characteristics of such a model. Ultimately a mathematical model is useful to summarize and predict the response and how it is changed by pathological, physiological or pharmacological interventions.

Keywords

Dioxide Depression Eter Aminophylline 

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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Denham S. Ward
    • 1
  1. 1.Departments of Anesthesiology and Electrical EngineeringUniversity of California, Los AngelesLos AngelesUSA

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