Nasal spirometery.

Nasal obstruction is a common symptom which is difficult to quantify clinically. Rhinomanometry, Acoustic Rhinometry and Forced Oscillation methods are available for estimating nasal resistance but, these require sophisticated machines. Because of limited availability of these techniques, this potential physiological measure has not been tapped fully for research and clinical purposes. Here, we describe the use of pulmonary spirometer with little modification for quantification of nasal flow. Nasal inspiratory and expiratory flow rates along with oral inspiratory and expiratory flow rates are used to derive different nasal resistance indices. This way of reporting nasal resistance is not new but, the data for these variables is currently not available in published literature. The reproducibility of nasal flow rates were tested as variation after one day and the interclass coefficient for inspiratory and expiratory nasal flow rates were found to be with in acceptable limits. Thus, nasal spirometery is able to describe the nasal resistance in a reliable manner and may be used to quantify nasal obstruction in pathological condition and also to study the physiological phenomenon like nasal cycle.