Role of oscillometry to diagnose obstructive airway diseases in patients who are unable to perform spirometry correctly

Abstract

BackgroundObstructive airway diseases (OAD) are an important contributor to the burden of respiratory diseases in India. The current gold standard to diagnose OAD is spirometry. However, spirometry is a forceful manoeuvre and many patients are unable to perform it as per correct standard acceptable criteria. Therefore, patients are sometimes misdiagnosed or undiagnosed leading to a delay in treatment. Therefore, a study was conducted with an aim to assess the role of forced oscillometry in diagnosing obstructive disease. MethodsA cross -sectional study was carried out from Jun 2019-Jun 2021 at a tertiary care chest centre, where consecutively 102 patients who were unable to perform spirometry correctly or had a contraindication to it were evaluated by oscillometry for OAD. ResultsOut of 102 patients who could not perform spirometry, OAD was detected in 84.4 %. 42.2 % of patients were diagnosed with asthma and similarly 42.2 % of patients were diagnosed to have Chronic obstructive pulmonary disease (COPD). The Mean (R5) Rrs at 5 Hz of the study population were 6.69 cmH2O/L/s for asthma, 5.91 cmH2O/L/s for COPD, and 3.16 cmH2O/L/s in a healthy population respectively. Mean R19 for Asthma, COPD and healthy individuals were 4.45 cmH20/L/s, 3.92 cmH20/L/s and 2.547 cmH20/L/s respectively. (X5) Xrs at 5 Hz of the study population were -3.16 cmH2O/Ls in asthma, −3.33 cmH2O/L/s in COPD, and −0.975 cmH2O/L/s in healthy individuals, respectively. ConclusionOscillometry is a pulmonary function test which can be performed easily and it can help in diagnosing OAD.