|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Pharyngeal dilator muscles are clearly important in the pathogenesis of obstructive sleep apnoea syndrome. Substantial data support the role of a local negative pressure reflex in modifying genioglossal activation across inspiration during wakefulness. Using a model of passive negative pressure ventilation, we have previously reported a tight relationship between varying intrapharyngeal negative pressures and genioglossal muscle activation (GGEMG) during wakefulness. In this study, we used this model to examine the slope of the relationship between epiglottic pressure (Pepi) and GGEMG, during stable NREM sleep and the transition from wakefulness to sleep. We found that there was a constant relationship between negative epiglottic pressure and GGEMG during both basal breathing (BB) and negative pressure ventilation (NPV) during wakefulness (slope GGEMG/Pepi 1.86 ± 0.3 vs. 1.79 ± 0.3 arbitrary units (a.u.) cmH2O-1). However, while this relationship remained stable during NREM sleep during BB, it was markedly reduced during NPV during sleep (2.27 ± 0.4 vs. 0.58 ± 0.1 a.u. cmH2O-1). This was associated with a markedly higher pharyngeal airflow resistance during sleep during NPV. At the transition from wakefulness to sleep there was also a greater reduction in peak GGEMG seen during NPV than during BB. These data suggest that while the negative pressure reflex is able to maintain GGEMG during passive NPV during wakefulness, this reflex is unable to do so during sleep. The loss of this protective mechanism during sleep suggests that an airway dependent upon such mechanisms (as in the patient with sleep apnoea) will be prone to collapse during sleep.
This article has been cited by other articles:
![]() |
V. K. Somers, D. P. White, R. Amin, W. T. Abraham, F. Costa, A. Culebras, S. Daniels, J. S. Floras, C. E. Hunt, L. J. Olson, et al. Sleep Apnea and Cardiovascular Disease: An American Heart Association/American College of Cardiology Foundation Scientific Statement From the American Heart Association Council for High Blood Pressure Research Professional Education Committee, Council on Clinical Cardiology, Stroke Council, and Council on Cardiovascular Nursing In Collaboration With the National Heart, Lung, and Blood Institute National Center on Sleep Disorders Research (National Institutes of Health) Circulation, September 2, 2008; 118(10): 1080 - 1111. [Full Text] [PDF] |
||||
![]() |
S. Cheng, J. E. Butler, S. C. Gandevia, and L. E. Bilston Movement of the tongue during normal breathing in awake healthy humans J. Physiol., September 1, 2008; 586(17): 4283 - 4294. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. K. Somers, D. P. White, R. Amin, W. T. Abraham, F. Costa, A. Culebras, S. Daniels, J. S. Floras, C. E. Hunt, L. J. Olson, et al. Sleep Apnea and Cardiovascular Disease: An American Heart Association/American College of Cardiology Foundation Scientific Statement From the American Heart Association Council for High Blood Pressure Research Professional Education Committee, Council on Clinical Cardiology, Stroke Council, and Council on Cardiovascular Nursing In Collaboration With the National Heart, Lung, and Blood Institute National Center on Sleep Disorders Research (National Institutes of Health) J. Am. Coll. Cardiol., August 19, 2008; 52(8): 686 - 717. [Full Text] [PDF] |
||||
![]() |
Y.-L. Lo, A. S Jordan, A. Malhotra, A. Wellman, R. A Heinzer, M. Eikermann, K. Schory, L. Dover, and D. P White Influence of wakefulness on pharyngeal airway muscle activity Thorax, September 1, 2007; 62(9): 799 - 805. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Pierce, D. White, A. Malhotra, J. K. Edwards, D. Kleverlaan, L. Palmer, and J. Trinder Upper airway collapsibility, dilator muscle activation and resistance in sleep apnoea Eur. Respir. J., August 1, 2007; 30(2): 345 - 353. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. P. Saboisky, J. E. Butler, R. B. Fogel, J. L. Taylor, J. A. Trinder, D. P. White, and S. C. Gandevia Tonic and Phasic Respiratory Drives to Human Genioglossus Motoneurons During Breathing J Neurophysiol, April 1, 2006; 95(4): 2213 - 2221. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Ryan and T. D. Bradley Pathogenesis of obstructive sleep apnea J Appl Physiol, December 1, 2005; 99(6): 2440 - 2450. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. P. White Pathogenesis of Obstructive and Central Sleep Apnea Am. J. Respir. Crit. Care Med., December 1, 2005; 172(11): 1363 - 1370. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Huang, D. P. White, and A. Malhotra The Impact of Anatomic Manipulations on Pharyngeal Collapse: Results From a Computational Model of the Normal Human Upper Airway Chest, September 1, 2005; 128(3): 1324 - 1330. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Huang, A. Malhotra, and D. P. White Computational simulation of human upper airway collapse using a pressure-/state-dependent model of genioglossal muscle contraction under laminar flow conditions J Appl Physiol, September 1, 2005; 99(3): 1138 - 1148. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. S. Doherty, P. Nolan, and W. T. McNicholas Effects of topical anesthesia on upper airway resistance during wake-sleep transitions J Appl Physiol, August 1, 2005; 99(2): 549 - 555. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. B Fogel, J. Trinder, D. P White, A. Malhotra, J. Raneri, K. Schory, D. Kleverlaan, and R. J Pierce The effect of sleep onset on upper airway muscle activity in patients with sleep apnoea versus controls J. Physiol., April 15, 2005; 564(2): 549 - 562. [Abstract] [Full Text] [PDF] |
||||
![]() |
R B Fogel, A Malhotra, and D P White Sleep {middle dot} 2: Pathophysiology of obstructive sleep apnoea/hypopnoea syndrome Thorax, February 1, 2004; 59(2): 159 - 163. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |