Pathophysiology of obstructive sleep apnoea

The pathophysiology of obstructive sleep apnoea (OSA) is complex and incompletely understood. A narrowed upper airway is very common among OSA patients, and is usually in adults due to nonspecific factors such as fat deposition in the neck, or abnormal bony morphology of the upper airway. Functional impairment of the upper airway dilating muscles is particularly important in the development of OSA, and patients have a reduction both in tonic and phasic contraction of these muscles during sleep when compared to normals. A variety of defective respiratory control mechanisms are found in OSA, including impaired chemical drive, defective inspiratory load responses, and abnormal upper airway protective reflexes. These defects may play an important role in the abnormal upper airway muscle responses found among patients with OSA. Local upper airway reflexes mediated by surface receptors sensitive to intrapharyngeal pressure changes appear to be important in this respect. Arousal plays an important role in the termination of each apnoea, but may also contribute to the development of further apnoea, because of reduction in respiratory drive related to the hypocapnia which results from postapnoeic hyperventilation. A cyclical pattern of repetitive obstructive apnoeas may result. A better understanding of the integrated pathophysiology of OSA should help in the development of new therapeutic techniques.

This article has been cited by other articles:

				M. G. Levitzky Using the pathophysiology of obstructive sleep apnea to teach cardiopulmonary integration Advan Physiol Educ, September 1, 2008; 32(3): 196 - 202. [Abstract] [Full Text] [PDF]

				W. T. McNicholas The nose and OSA: variable nasal obstruction may be more important in pathophysiology than fixed obstruction Eur. Respir. J., July 1, 2008; 32(1): 3 - 8. [Full Text] [PDF]

				S. Kiekens, Veva De Groot, T. Coeckelbergh, M.-J. Tassignon, P. van de Heyning, Wilfried De Backer, and J. Verbraecken Continuous Positive Airway Pressure Therapy Is Associated with an Increase in Intraocular Pressure in Obstructive Sleep Apnea Invest. Ophthalmol. Vis. Sci., March 1, 2008; 49(3): 934 - 940. [Abstract] [Full Text] [PDF]

				W. T. McNicholas Diagnosis of Obstructive Sleep Apnea in Adults Proceedings of the ATS, February 15, 2008; 5(2): 154 - 160. [Abstract] [Full Text] [PDF]

				W. T. McNicholas Cardiovascular outcomes of CPAP therapy in obstructive sleep apnea syndrome Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2007; 293(4): R1666 - R1670. [Abstract] [Full Text] [PDF]

				S. K. Sharma, S. Kumpawat, A. Banga, and A. Goel Prevalence and risk factors of obstructive sleep apnea syndrome in a population of delhi, India. Chest, July 1, 2006; 130(1): 149 - 156. [Abstract] [Full Text] [PDF]

				M. Poulain, M. Doucet, G. C. Major, V. Drapeau, F. Series, L.-P. Boulet, A. Tremblay, and F. Maltais The effect of obesity on chronic respiratory diseases: pathophysiology and therapeutic strategies. Can. Med. Assoc. J., April 25, 2006; 174(9): 1293 - 1299. [Abstract] [Full Text] [PDF]

				A. S. Jordan, A. Wellman, J. K. Edwards, K. Schory, L. Dover, M. MacDonald, S. R. Patel, R. B. Fogel, A. Malhotra, and D. P. White Respiratory control stability and upper airway collapsibility in men and women with obstructive sleep apnea J Appl Physiol, November 1, 2005; 99(5): 2020 - 2027. [Abstract] [Full Text] [PDF]

				M Dematteis, P Levy, and J-L Pepin A simple procedure for measuring pharyngeal sensitivity: a contribution to the diagnosis of sleep apnoea Thorax, May 1, 2005; 60(5): 418 - 426. [Abstract] [Full Text] [PDF]

				M.I. Polkey, R. Farre, and A.T. Dinh-Xuan Respiratory monitoring: revisiting classical physiological principles with new tools Eur. Respir. J., November 1, 2004; 24(5): 718 - 719. [Full Text] [PDF]

				A. Stammnitz, A. Jerrentrup, T. Penzel, J.H. Peter, C. Vogelmeier, and H.F. Becker Automatic CPAP titration with different self-setting devices in patients with obstructive sleep apnoea Eur. Respir. J., August 1, 2004; 24(2): 273 - 278. [Abstract] [Full Text] [PDF]

				J L Kiely, P Nolan, and W T McNicholas Intranasal corticosteroid therapy for obstructive sleep apnoea in patients with co-existing rhinitis Thorax, January 1, 2004; 59(1): 50 - 55. [Abstract] [Full Text] [PDF]

				K. D. O'Halloran, M. McGuire, T. O'Hare, and A. Bradford Chronic Intermittent Asphyxia Impairs Rat Upper Airway Muscle Responses to Acute Hypoxia and Asphyxia* Chest, July 1, 2002; 122(1): 269 - 275. [Abstract] [Full Text] [PDF]

				F. Chung and C. Imarengiaye Management of sleep apnea in adults Can J Anesth, June 1, 2002; 49(90001): R13 - 13. [Full Text] [PDF]

				W. Hildebrandt, S. Alexander, P. Bartsch, and W. Droge Effect of N-acetyl-cysteine on the hypoxic ventilatory response and erythropoietin production: linkage between plasma thiol redox state and O2 chemosensitivity Blood, March 1, 2002; 99(5): 1552 - 1555. [Abstract] [Full Text] [PDF]

				J. Harbison, P. O'Reilly, and W. T. McNicholas Cardiac Rhythm Disturbances in the Obstructive Sleep Apnea Syndrome : Effects of Nasal Continuous Positive Airway Pressure Therapy Chest, September 1, 2000; 118(3): 591 - 595. [Abstract] [Full Text] [PDF]

				J. B. SCHELLENBERG, G. MAISLIN, and R. J. SCHWAB Physical Findings and the Risk for Obstructive Sleep Apnea . The Importance of Oropharyngeal Structures Am. J. Respir. Crit. Care Med., August 1, 2000; 162(2): 740 - 748. [Abstract] [Full Text] [PDF]

				L. Parrino, A. Smerieri, M. Boselli, M. C. Spaggiari, and M. G. Terzano Sleep reactivity during acute nasal CPAP in obstructive sleep apnea syndrome Neurology, April 25, 2000; 54(8): 1633 - 1640. [Abstract] [Full Text] [PDF]

				K.G. van Houwelingen, R. van Uffelen, and A.C.M. van Vliet The sleep apnoea syndromes Eur. Heart J., June 2, 1999; 20(12): 858 - 866. [PDF]

				R. FARRE, R. PESLIN, J. M. MONTSERRAT, M. ROTGER, and D. NAVAJAS Flow-dependent Positive Airway Pressure to Maintain Airway Patency in Sleep Apnea-Hypopnea Syndrome Am. J. Respir. Crit. Care Med., June 1, 1998; 157(6): 1855 - 1863. [Abstract] [Full Text] [PDF]