Measurements of nasal airflow and patency: a critical review with emphasis on the use of peak nasal inspiratory flow in daily practice

Objective measures can be used to assist the clinician to diagnose and treat nasal obstruction and also to quantify nasal obstruction in research. Objective measurements of nasal obstruction are as important as objective measurements of lungfunction. PNIF, AR, and RM, with their specific peculiarity, assess different aspects of nasal obstruction. From the studies available in literature, it seems that these methods roughly correlate with each other and that all of them can be alternatively utilized very well in research as well as in clinical practice This review describes the various methods that can be used to measure nasal patency, airflow and resistance, mainly peak nasal inspiratory flow, rhinomanometry, and acoustic rhinometry. PNIF has been demonstrated to be reproducible and as good an indication of objective nasal patency as formal rhinomanometry and has the advantage to be cheap, simple, suitable for serial measurements and for home use even in the paediatric population. PNIF normative data are available for children, adults, and elderly subjects and the availability of unilateral PNIF normal values allows evaluation of nasal sides separately. Just as in the lower airways, objective and subjective evaluation give different information that together optimalize the diagnosis and treatment of our patients. We argue that PNIF should be used regularly in every outpatient clinic that treats patients with nasal obstruction. This article is protected by copyright. All rights reserved.