Nasopharyngeal tract length measurement in infants

Acta Paediatr Taiwan. Mar-Apr 2002;43(2):82-5.


Artificial nasopharyngeal (NP) airway is a common device used to secure upper airway patency. The proper length of its insertion is important, especially in infants. The purpose of this study is to measure and compare the endoscopic and the anthropometric measurements of NP length in infants.

Material and methods: We collected data from 413 infants who received flexible fiberoptic endoscopy. Endoscopic measurement length is from the nostril to the vocal cord (N-V distance). Anthropometric measurement length is from the nose tip to the earlobe. We stratified the infants into four groups by body weight and compared the difference between the two measurement methods.

Results: The mean length of the endoscopic measurement is compatible to the anthropometric measurement in all four groups. There is a statistically significant correlation between the N-V distance and the body length (p = 0.0001, r = 0.83), the body weight (p = 0.0001, r = 0.81), and the age (p = 0.0001, r = 0.64).

Conclusion: The anthropometric measurement of nasopharyngeal airway length is nearly identical to the endoscopic measurement.

MeSH terms

  • Body Height
  • Body Weight
  • Endoscopy
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Nasopharynx / anatomy & histology*
  • Prospective Studies
  • Regression Analysis