An Anthropometric Measurements of the Upper Airway Using Fiberoptic Laryngoscope in Korean Adults

Lee, Sang Kyi; Yoo, Chun Won

Abstract

Introduction
An anthropometric distance is crucial for an easy endotracheal intubation and correct placement of endotracheal tube in the trachea. There may be a racial difference of the anthropometric measurement. So we measured the anthropometric distances of the upper airway in Korean adult patients.
METHODS
A standard anesthetic induction and maintenance was performed in 100 adult patients following endotracheal intubation. Various anthropometric measurements were determined while the patients head were in a neutral position. Thyromental and sternomental distance were measured. A distance from upper central incisor to carina or cricoid cartilage was directly measured using fiberoptic laryngoscope. However, the length from upper central incisor to midtrachea & the cricoid cartilage-carina distance were indirectly calculated from the above measured distances. Correlation analyses were also performed between age, height, or weight and the above measured anthropometric distances.
RESULTS
The mean distances from upper central incisor to carina, cricoid cartilage or midtrachea were 25.5+/-1.8, 13.9+/-1.9, or 19.8+/-1.8cm respectively. The mean distance from cricoid cartilage to carina was 11.6+/-1.4cm. Thyromental and thyrosternal distance were 6.6+/-0.9 and 15.7+/-1.5cm respectively. All mean anthropometric distances of male were longer than those of female patients. Thirty-eight patients (38%) had the thyromental distance < or = 6cm while one patient (1%) had thyrosternal distance < or = 12.5cm. A good correlation (r< or =0.6) was observed between height and upper central incisor-carina distance.
CONCLUSIONS
This study suggests that these measured anthropometric data are useful for an easy endotracheal intubation and accurate endotracheal placement in the trachea.