DYNAMIC MECHANICAL PROPERTIES OF THE CANINE TRACHEA IN SITU (IMPEDANCE, PROPAGATION)

Despite the suggested role of airway distensibility in numerous respiratory functions, very little information exists about airway dynamic mechanical properties. Without this information, hypotheses about the physiologic function of airway smooth muscle are difficult to substantiate.

My thesis research presents a method to measure wall impedance and propagation characteristics of the canine trachea. This technique is used to characterize the dynamic mechanical properties of the canine trachea in situ, to evaluate the effect of changes in smooth muscle tone on these properties, and to assess the functional effect of the distensible tracheal wall on high frequency respiratory mechanics. Tracheal wall impedance (Z(,w)) and propagation coefficient ( ) data from 2 - 96 Hz.

The thesis work is presented in five sections: (1) Introduction and literature review; (2) Theory of measurement; (3) In-situ Z(,w) and (4) The effect of pharmacological and neural alterations of smooth muscle tone on tracheal mechanical properties; (5) Airway mechanics during high frequency ventilation.