Citation Information :
Amra B, Golshan M, Bahaee FS, Zadegan ZF. Impulse Oscillometry in Obstructive Sleep Apnea Syndrome. Indian Sleep Med 2007; 2 (4):126-129.
Question of Study: In this study, we examined the oral airway resistance during wakefulness in different degrees of severity of OSAS (Obstructive sleep apnea) with Impulse Oscillometry and investigated whether these changes have any correlation with sleep apnea severity parameters.
Methods: All subjects who were admitted in sleep lab to undergo overnight sleep study were enrolled. Pulmonary function testing and measurement of oral airway resistance [resistance (R) and reactance (X)] by Impulse Oscillometry were done for every subjects. The average number of episodes of apnea and hypopnea per hour of sleep (the apnea-hypopnea index, AHI) were calculated. An AHI of 5 –29 represented mild/moderate OSAS and an AHI > 30 represented severe OSAS.
All parameters were compared between controls and mild/moderate and severe OSAS groups by using one way ANOVA methods.
Results: Patients with severe OSA had significantly lower FVC (P < .05) than healthy subjects; however, the values were within the normal range. Also these Patients had a higher resistance at 5 Hz (P < .05) and lower reactance than control(P < .05).
Conclusion: Impulse oscillometry data may be good predictor of OSA in Iranian patients with sleep apnea.
Yucel A, Unlu M, Haktanir A, Acar M, Fidan F (2005) Evaluation of the Upper Airway Cross-sectional Area Changes in Different Degrees of Severity of Obstructive Sleep Apnea Syndrome: Cephalometric and Dynamic CT Study. Am. J. Neuroradiol; 26(10): 2624 – 2629
Fitzpatrick M, McLean H, Urton A, Tan A, O'Donnell D, Driver H. Effect of nasal or oral breathing route on upper airway resistance during sleep. Eur Respir J 2003;22:827– 832.
Koutsourelakis, E. Vagiakis, C. Roussos, and S. Zakynthinos. Obstructive sleep apnoea and oral breathing in patients free of nasal obstruction. Eur Respir J 2006 28: 1222- 1228.
Navajas D, Farré R, Rotger M, Badia R, Puig-de-Morales M, Montserrat JM (1998) Assessment of airflow obstruction during CPAP by means of forced oscillation in patients with sleep apnea. Am J Respir Crit Care Med 157:1526–1530
Rechtschaffen A, Kales A. eds. A Manual of Standardized Terminology, Techniques and Scoring System for Sleep Stages of Human Subjects. Bethesda, National Institutes of Health, 1968
Lam B, Ooi CGC, Peh WCG, et al. Computed tomographic evaluation of the role of craniofacial and upper airway morphology in obstructive sleep apnea in Chinese. Resp Med 2004;98:301–307
Golshan M, Nematbakhsh M, Amra B, Crapo RO (2003). Spirometric reference values in a large Middle Eastern population. Eur Respir J; 22(3):529-34 8 Oostveeen E, MacLeod D, Lorino H, Farr R, Hantos Z, Desager K, et al(2003). The forced oscillation technique in clinical practice: methodology, recommendations and future developments. Eur Respir J 2003;22:1026-41.
Badia JR, Farré R, Montserrat JM, Ballester E, Hernandez L, Rotger M, Rodriguez-Roisin R, Navajas D (1998) Forced oscillation technique for the evaluation of severe sleep apnoea/hypopnoea syndrome: a pilot study. Eur Respir J 11:1128–1134
Badia JR, Farré RO, John Kimoff R, Ballester E, Hernandez L, Rotger M, Navajas D, Montserrat JM (1999) Clinical application of the forced oscillation technique (FOT) for CPAP titration in the sleep apnea/hypopnea syndrome. Am J Respir Crit Care Med 160:1550–1554
Amis TC, ONeill N, Wheatley JR (1999) Oral airway flow dynamics in healthy humans. J Physiol 515:293–298
Kawano K, Usui N, Kanazawa H, Hara I (1996) Changes in nasal and oral respiratory resistance before and after uvulopalatopharyngoplasty. Acta Otolaryngol [Suppl] 523:236–238
Battagel JM, Johal A (2000). A cephalometric comparison of normal weight and obese subjects with obstructive sleep apnoea. Radiography;6:283–292