The relationship of peak inspiratory airflow to subjective airflow in the nose.

A prospective study of 145 patients presenting for nasal surgery was designed to examine the relationship of peak nasal inspiratory airflow (PNIF) to subjective nasal airway patency (SNA). Patients admitted for surgery filled in a self-assessment Questionnaire and PNIF measurements were taken. Six weeks post surgery the procedure was repeated. The patients were divided into four operative groups and the results analysed accordingly. Improvement in SNA was noted in 80-96% of patients and PNIF improved in 60-83%. However, PNIF decreased in 17-40% of patients who felt they were improved. Statistical analysis using Spearman's Rank Correlation test showed no correlation between SNA and PNIF. Despite the well recognized problems of assessing subjective sensation of nasal airflow, we feel this study casts doubt on the usefulness of PNIF in routine clinical practice.