HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free All Versions of this Article: 97/1/339    most recent 00907.2003v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (19) Citing Articles via Google Scholar Google Scholar Articles by Isono, S. Articles by Nishino, T. Search for Related Content PubMed PubMed Citation Articles by Isono, S. Articles by Nishino, T.

Influences of head positions and bite opening on collapsibility of the passive pharynx

Department of Anesthesiology (B1), Graduate School of Medicine, Chiba University, Chiba, 260-8670, Japan

Submitted 25 August 2003 ; accepted in final form 1 March 2004

A collapsible tube surrounded by soft material within a rigid box was proposed as a two-dimensional mechanical model for the pharyngeal airway. This model predicts that changes in the box size (pharyngeal bony enclosure size anatomically defined as cross-sectional area bounded by the inside edge of bony structures such as the mandible, maxilla, and spine, and being perpendicular to the airway) influence patency of the tube. We examined whether changes in the bony enclosure size either with head positioning or bite opening influence collapsibility of the pharyngeal airway. Static mechanical properties of the passive pharynx were evaluated in anesthetized, paralyzed patients with sleep-disordered breathing before and during neck extension with bite closure (n = 11), neck flexion with bite closure (n = 9), and neutral neck position with bite opening (n = 11). Neck extension significantly increased maximum oropharyngeal airway size and decreased closing pressures of the velopharynx and oropharynx. Notably, neck extension significantly decreased compliance of the oropharyngeal airway wall. Neck flexion and bite opening decreased maximum oropharyngeal airway size and increased closing pressure of the velopharynx and oropharynx. Our results indicate the importance of neck and mandibular position for determining patency and collapsibility of the passive pharynx.

obstructive sleep apnea; upper airway; closing pressure; neck positions; mouth opening

This article has been cited by other articles:

				K. Kairaitis, L. Howitt, J. R. Wheatley, and T. C. Amis Mass loading of the upper airway extraluminal tissue space in rabbits: effects on tissue pressure and pharyngeal airway lumen geometry J Appl Physiol, March 1, 2009; 106(3): 887 - 892. [Abstract] [Full Text] [PDF]

				M. Younes Role of respiratory control mechanisms in the pathogenesis of obstructive sleep disorders J Appl Physiol, November 1, 2008; 105(5): 1389 - 1405. [Abstract] [Full Text] [PDF]

				Y. Tagaito, S. Isono, J. E. Remmers, A. Tanaka, and T. Nishino Lung volume and collapsibility of the passive pharynx in patients with sleep-disordered breathing J Appl Physiol, October 1, 2007; 103(4): 1379 - 1385. [Abstract] [Full Text] [PDF]

				A. R. Schwartz, J. Kirkness, and P. Smith Extraluminal tissue pressure: what does it mean? J Appl Physiol, January 1, 2006; 100(1): 5 - 6. [Full Text] [PDF]

				K. Kairaitis, R. Stavrinou, R. Parikh, J. R. Wheatley, and T. C. Amis Mandibular advancement decreases pressures in the tissues surrounding the upper airway in rabbits J Appl Physiol, January 1, 2006; 100(1): 349 - 356. [Abstract] [Full Text] [PDF]