Online measurement of nasal NO.

Although there are numerous publications on exhaled NO, the study of nasal NO measurement has been limited due to lack of a standardized technique of measurement until very recently. The standardization of techniques opens the way for the collection by numerous centers of comparable data from normal subjects and those with disease states. Of late, it has been determined that NO plays a critical role as an inflammatory mediator in the upper and lower respiratory airways. In order to properly take measurements and verify whether a treatment needs to be pursued due to high levels of nasal NO, it is imperative to determine whether a fixed flow rate needs to exist. With the determination of whether NO is flow dependent, the calculation of parameters aside from concentrations, namely DNO, the diffusion factor for NO across nasal membranes, and Cw, the wall concentration of nasal NO can be determined and can be used as separate markers in different diseases. The purpose of this study is to evaluate a set of normal and variable data at various fixed flow rates and form an equation that can measure nasal concentration as correlated with the ability of NO to across the membranes. This can in tam show the direction of NO, as marked by the level of diffusivity, in the nasal cavity and its association with certain upper airway dysfunctions and diseases.

Jane Muchnik, Cherry Creek High School.