Microcirculation impedance analysis in cat lung

An analysis of pulsatile microcirculation in cat lung, with special attention to the pulmonary microvascular impedance, is presented. A theoretical calculation is made on the basis of a complete set of experimental data on the morphology and elasticity of cat's pulmonary capillary sheets. The transfer matrix of the pulmonary microvascular impedance is obtained. The input impedance at the capillary entrance and exit are determined. The input impedance at the pulmonary arterial trunk is compared under various physiological conditions. It is shown that although the impact of pulmonary microcirculation on the relationship between the steady mean flow and pressure in the pulmonary arteries and veins is decisively large, the influence of the alveolar microcirculation on the input impedance at the pulmonary arterial trunk is small.