Partitioning Nasal Airway Resistance in Normal Adults

A rhinomanometric method that partitions nasal airway resistance into its nasal cavity and velopharyngeal components is described. Nasal cavity resistance, velopharyngeal resistance and total nasal airway resistance is reported for 20 normal subjects (10 women and 10 men). During expiration, mean nasal cavity resistance for women (1.52 cm H₂O/[liters per second] L/s) was 76.3% and mean velopharyngeal resistance (.64 cm H₂O/L/s) constituted 23.7% of the total nasal airway resistance. For men, mean nasal cavity resistance (1.50 cm H₂O/L/S) made up 70.2% and mean velopharyngeal resistance (.85 cm H₂O/L/S) was 29.8% of the total nasal airway resistance. During inspiration, the mean nasal cavity resistance for women (1.47 cm H₂O/L/s) was 75.8% and mean velopharyngeal resistance (.44 cm H₂O/L/s) was 24.2% of total nasal airway resistance. For men, mean nasal cavity resistance (1.30 cm H₂O/L/s) constituted 73.9% and mean velopharyngeal resistance (.83 cm H₂O/L/s) made up 26.1% of total nasal airway resistance. The importance of this method in clinical practice is discussed.