General Medical Information

Nasal Aerodynamics

Thomas V. Mccaffrey

A basic knowledge of the characteristics of nasal airflow is necessary to understand the applications and limitations of rhinomanometry. Airflow through the nose follows the basic physical laws first elaborated by Poiseuille and Reynolds. However, airflow in the nose is complicated by the irregular contour of the nasal cavity, areas of marked constriction and abrupt changes in direction of airflow, regions with collapsible segments, and areas in which the dimensions of the airway are under muscular and vascular control. These complicating factors impose limitations on interpretation of nasal resistance measurements, because the nasal airway cannot be represented as an ideal tube, as assumed by the simplest physical law of fluid flow.