Nasal peak inspiratory flow (NPIF) as a diagnostic tool for differentiating decongestable from structural nasal obstruction
Reviewed by Lakhbinder Pabla

Identification of the cause of nasal obstruction is critical before surgical intervention such as septoplasty. This study assesses changes in nasal peak inspiratory flow (NPIF) as a tool for discriminating decongestable versus structural obstruction. A cross-sectional study of 52 patients (24 with decongestable, 28 with structural obstruction) undergoing nasal airflow assessment was performed. Rhinomanometry, nasal obstruction visual analogue score (VAS) and NPIF were performed pre- and post-decongestion. Population groups were defined with decongestable or structural obstruction by relative post-decongestion changes in airways resistance and symptoms. Pre- and post-decongestion NPIF were similar between groups. Absolute and percentage NPIF changes were larger with decongestable versus structural obstruction. Sensitivity and specificity for predicting decongestable obstruction were 75.0% and 60.7% for NPIF increase >20L/min; 75.0% and 64.3% for NPIF increase >20%. The respective positive predictive values were 62.1% and 64.3%. The study concluded that the NPIF increase after decongestion is larger with decongestable than structural obstruction but NPIF alone cannot discriminate the two conditions and does not replace more formal assessment.

Nasal peak inspiratory flow (NPIF) as a diagnostic tool for differentiating decongestable from structural nasal obstruction.
Chin D, Marcells G, Malek J, et al.
RHINOLOGY
2014;52(2):116-21.