Contribution of large airways to respiratory system input impedance

Mechanical properties of the human respiratory system are studied using input-output pressure-flow relationships. This input impedance data is fitted to lumped electrical analogs of the system, and the estimated parameters are then assigned a physiological significance. The authors present a technique to refine the interpretation of these parameters. They independently obtain geometrical information describing the large airways and calculate its contribution to the system impedance. Simulations show that this part acts as a resistive-inertial element.<>