Proportion of Lung Hyperinflation In Patients With Persistent Asthma In Persahabatan Hospital Jakarta Using Multiple Breath N2-Washout

Background: In asthma, small airway dysfunction and inflammation may induce significant lung hyperinflation. The aim of the study is to discover proportion hyperinflation in patient with persistent asthma Persahabatan Hospital Jakarta. 
 Method: A cross sectional descriptive analysis was done Asthma clinic from September-November 2016. Forty-five subjects were recruited consecutively. Interview, physical examination, chest x-ray (CXR), spirometry multiple breath N2-washout (MBW) performed. Lung defined as a residual volume /total capacity (RV/TLC%) above upper limit normal.
 Results: patients 17,8% (8 45 subjects).
 Median RV milliliter 1230 (570-2860). functional (FRC) 1730 (970-3990). TLC 3310 (2490-6350). Mean RV/TLC ratio 36,39% (SD±8,86). FRC/TLC 52,86% (SD ±6,85). There correlation between forced expiratory 1 second (FEV1%) value decline FEV1 <60% increased risk by 8,46 (95%CI=1,155-61,98; p=0,036). no age, gender, smoking habit, body mass index (BMI), ACT score, severity duration steroid inhalation use, exacerbation history last 12-months emphysematous CXR (p>0,05). Conclusions: Jakarta 17,8%. associated degree obstruction.