Methods of Assessing Respiratory Impedance During Flow Limited and Non-Flow Limited Inspirations

  • S. A. Tuck
  • J. E. Remmers
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 450)


We are interested in characterizing the mechanical load on the respiratory system of obese pigs during wakefulness and sleep. These animals exhibit sleep-disordered breathing, manifest by characteristics similar to the human obstructive sleep apnea/hypopnea syndrome including inspiratory flow limitation (FL). During inspiratory FL, airflow becomes dissociated from the driving pressure; under these conditions, traditional measures such as resistance may not be suitable for describing mechanical load. Therefore, the purpose of this study was to mathematically describe the resistive pressure-airflow relationship during FL and non-FL inspirations. To accomplish this, two models of the resistive pressure-inspiratory airflow relationship during FL and two models for non-FL inspirations were compared for their ability to fit experimental data. The parameters of these models were then correlated with airway resistance.


Order Equation Flow Limitation Driving Pressure Resistive Pressure Differential Pressure Transducer 
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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • S. A. Tuck
    • 1
  • J. E. Remmers
    • 1
  1. 1.Faculty of MedicineUniversity of CalgaryCalgaryCanada

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