RESUMO
Impulse oscillometry provides useful clinical information that prominently includes functional assessment of small, peripheral airway behavior beyond that available from commonly used pulmonary function tests [PFT]. The aim of this study was to assess the role of impulse oscillometry in assessment of airway obstruction in smokers and ex-smokers. Sixty subjects divided into three groups [asymptomatic smokers, ex-smokers and non smoker healthy subjects as a controls] all were assessed by spirometry and IOS. Based on the IOS results in smokers, there was 17 negative cases and only 3 diseased cases, the calculated Specificity of spirometry [ability to detect negative cases as negative] 100%, while its sensitivity [ability to detect diseased cases as diseased] was only 33% as it was able to detect one diseased case from a total of three cases .In ex-smokers, there was 13 negative cases and only 7 diseased cases, the calculated Specificity of spirometry [ability to detect negative cases as negative] 100%, while its sensitivity [ability to detect diseased cases as diseased] was only 42.8% as it was able to detect 3 diseased case from a total of 7 cases. In controls, there was 18 negative cases and two diseased cases, the calculated Specificity of spirometry [ability to detect negative cases as negative] 100%, while its sensitivity [ability to detect diseased cases as diseased] was 50% as it was able to detect 1 diseased case from a total of 2 cases. IOS is an effective, easy to perform, and a non invasive method for the assessment of airway obstruction in obstructive pulmonary disorders. Although, there is no significant difference between impulse oscillometry and spirometry parameters in early detection of airway obstruction in smokers and ex-smokers groups