ABSTRACT
Introduction: Obstructive sleep apnea syndrome is the mostcommon sleep disordered breathing (SDB) and is associatedwith recurrent episodes of upper airway (UA) collapse duringsleep. Arousal from sleep is required to re-establish the airwaypatency. Patients with OSAS have various structural andfunctional abnormalities of the upper airway during sleep,which may reflect on their pulmonary function tests.Material and methods: We performed spirometry in 50diagnosed OSAS patients. Spirometric indices like FEF50/FIF50 >1 and saw tooth appearance of FV loops were studied.Their association with OSA and grades of OSA was evaluatedusing statistical analysis.Results: It was found that these spirometric indices werecommon in OSAS patients but their association with grades ofOSA were not statistically significant.Conclusion: Spirometry findings can point toward diagnosisof OSA but these findings are absent in most OSA patients.