[Use of nasal flowmeter to measure nasal patency]

We determined nasal peak flow using a peak flowmeter with a face mask (PALROD peak expiratory flowmeter) and nasal airway patency with an anterior rhinomanometer (Nihon Koden MPR-1100) at a minimum time interval in the same individual. We compared the values obtained by two kinds of measurements to evaluate the usefulness of the peak flowmeter for nasal airway patency. In this study, the nasal patencies were experimentally changed and measured in 30 patients using alpha-1 stimulant spray and in 25 patients with nasal allergy using nasal provocation of antigens. We also measured the natural circadian changes of nasal patency in 21 patients with nasal allergy and in 18 normal persons every two hours from 8:00 A.M. to 8:00 P.M. and from 9:00 A.M. to 9:00 P.M., respectively. As a result, we found close correlations between percent change of the peak flow and the nasal airway patency measured after spraying alpha-1 stimulant (r = 0.699, p less than 0.01), after antigen provocation (r = 0.585, p less than 0.01), and during circadian change (r = 0.464, p less than 0.01 in normal persons and r = 0.251, p less than 0.05 in allergy patients). In conclusion, peak flowmeter is handier and cheaper than rhinomanometer and is useful in evaluating the effect of vasoconstrictors and nasal provocation on nasal patency and in measuring the circadian changes of nasal patency. Since nasal secretion in the nose affects the measurement of peak flow, it should be removed as much as possible immediately before the flowmeter is used.