Nasal airway resistance in the newborn.

The present study aimed to provide normative data for nasal airway resistance in the newborn. Anterior rhinomanometry was performed on 17 full term Caucasian infants aged 1 to 4 days, birthweight 3100 to 4150 g. No sedation or decongestion was performed. Average unilateral nasal resistance was 4.86 kPa/l/s (SD = 2.41) at a pressure threshold of 75 Pa. Average nasal resistance calculated from the right and left side recordings was 2.14 kPa/l/s (SD = 0.77). This corresponds to 21.8 cm H2O/l/s (SD = 7.9). The nasal resistance of the newborn thus is approximately 10 times that of the adult.