New acoustic method for detecting upper airway obstruction in patients with sleep apnoea

  1. Elaine M. STOCKX1,*,
  2. Peter CAMILLERI1,
  3. Elizabeth M. SKUZA1,
  4. Thomas CHURCHWARD2,
  5. Julie M. HOWES2,
  6. Michael HO2,
  7. Timothy MCDONALD2,
  8. Nicholas FREEZER2,
  9. Garun HAMILTON2,
  10. Malcolm H. WILKINSON1,
  11. Philip J. BERGER1

Article first published online: 26 JAN 2010

DOI: 10.1111/j.1440-1843.2009.01689.x

Issue

Respirology

Respirology

Volume 15, Issue 2, pages 326–335, February 2010

Additional Information

How to Cite

STOCKX, E. M., CAMILLERI, P., SKUZA, E. M., CHURCHWARD, T., HOWES, J. M., HO, M., MCDONALD, T., FREEZER, N., HAMILTON, G., WILKINSON, M. H. and BERGER, P. J. (2010), New acoustic method for detecting upper airway obstruction in patients with sleep apnoea. Respirology, 15: 326–335. doi: 10.1111/j.1440-1843.2009.01689.x

Author Information

  1. 1

    Ritchie Centre for Baby Health Research, Monash Institute of Medical Research, Monash University, and

  2. 2

    Department of Respiratory and Sleep Medicine, Monash Medical Centre, Clayton, Victoria, Australia

*Elaine M. Stockx, Ritchie Centre for Baby Health Research, Monash Institute of Medical Research, Monash Medical Centre, Level 5, 246 Clayton Road, Clayton, Vic. 3168, Australia. Email: elaine.stockx@med.monash.edu.au

Publication History

  1. Issue published online: 26 JAN 2010
  2. Article first published online: 26 JAN 2010
  3. Received 28 July 2009; invited to revise 7 September 2009, 30 September 2009; revised 10 September 2009, 30 September 2009; accepted 12 October 2009 (Associate Editor: Robin Taylor).

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

View Full Article (HTML) Get PDF (638K)

Keywords:

  • acoustic method;
  • diagnosis of apnoea;
  • obstructive sleep apnoea;
  • polysomnography;
  • sound attenuation

This article investigates a new acoustic device to assess the behaviour of the upper airway in patients with OSA. Currently there is no simple non-invasive method to perform such measurements. As such this paper describes the device in probing the patency of the airway during sleep and increasing the efficiency of diagnosing OSA.

ABSTRACT

Background and objective:  OSA is a common disorder resulting in health and economic burdens. Currently identifying OSA in patients involves expensive techniques that require overnight studies in a laboratory setting with qualified staff. This paper tests a new acoustic device (AirwayClear (AC)) for assessing upper airway patency in human subjects with OSA. We hypothesize that obstructive apnoeas would be detected equally well with AC and polysomnography (PSG).

Methods:  Twenty-three patients with severe OSA underwent an overnight CPAP titration study. We introduced pseudorandom noise (600–1200 Hz) using AC to the patient's nasal mask during 1 h of subtherapeutic CPAP. AC determined a measure of airway patency based on the level of pseudorandom noise reaching a sternal notch sensor. The ability of AC to detect obstructive respiratory events was compared with standard PSG.

Results:  Three hundred and twenty-two obstructive events (obstructive and mixed apnoeas) were identified by PSG. AC scored 80% as complete obstructions and 16% as partial obstructions. Conversely, AC detected 281 complete obstructions. PSG recognized 84% as apnoeas and scored 11% as hypopnoeas. Of the 204 hypopnoeas identified with PSG, AC indicated the airway was partially or completely obstructed in 69% of patients. A Bland–Altman analysis for the apnoeas from the two measures showed a mean difference of 2.3 events/h and 95% confidence intervals of ±15.5 events/h.

Conclusions:  We conclude that AC is able to track airway patency and to identify airway closure in patients with OSA.

View Full Article (HTML) Get PDF (638K)