Korean J Anesthesiol.  1996 Dec;31(6):733-738. 10.4097/kjae.1996.31.6.733.

Metric Study of Upper Airway and Trachea in Nomal Korean Adults uing Fiberoptic Bronchoscopy: Study of endotracheal tube fixation positioning in adults

• Park S
• Kim C
• Jung I

• KMID: 2236905
• DOI: http://doi.org/10.4097/kjae.1996.31.6.733

Abstract

BACKGROUND: Neck flexion risks endobroncheal intubation when the tracheal tube is not in the proper position. So accurate knowledge of upper airway length is required to prevent malpositioning of endotracheal tubes. Therefore we evaluated the length of various portions of upper airway in Korean adults (n=500) who had no abnormality of upper airway.
METHODS
Five hundred patients, composed of 198 males and 302 females who underwent elective surgery, were included in this study. After endotracheal tube was placed under general anesthesia, we measured the distance from tube machine-end to upper incisor (value 1), from tube machine-end to inferior margin of cricothyroid membrane (value 2), and from tube machine-end to carina (value 3) by means of fiberoptic bronchoscopy.
RESULTS
The mean length between upper incisor and inferior margin of cricothyroid membrane (value 2 - value 1) was 12.7 cm in males and 11.6 cm in females, while the mean length between superior margin of cricoid cartilage and carina (value 3 - value 2) was 12.9 cm in males and 11.3 cm in females. So the mean length between upper incisor and the mid portion of trachea was nearly 19.6 cm in males and 17.7 cm in females.
CONCLUSIONS
We believe that, based on the findings in this study, the safety length for endotracheal tube fixation is 20 cm in Korean adult males and 18 cm in Korean adult females.

Keyword

Airway trachea; Anatomy airway; Anesthetic techniques intubation; Equipment bronchoscopes

MeSH Terms

Adult*
Anesthesia, General
Bronchoscopy*
Cricoid Cartilage
Female
Humans
Incisor
Intubation
Male
Membranes
Neck
Trachea*