25654309
BACKGROUND	Lung volume reduction ( LVR ) techniques improve lung function in selected patients with emphysema , but the impact of LVR procedures on the asynchronous movement of different chest wall compartments , which is a feature of emphysema , is not known .
METHODS	We used optoelectronic plethysmography to assess the effect of surgical and bronchoscopic LVR on chest wall asynchrony .
METHODS	Twenty-six patients were assessed before and 3 months after LVR ( surgical [ n = 9 ] or bronchoscopic [ n = 7 ] ) or a sham/unsuccessful bronchoscopic treatment ( control subjects , n = 10 ) .
METHODS	Chest wall volumes were divided into six compartments ( left and right of each of pulmonary ribcage [ Vrc , p ] , abdominal ribcage [ Vrc , a ] , and abdomen [ Vab ] ) and phase shift angles ( ) calculated for the asynchrony between Vrc , p and Vrc , a ( RC ) , and between Vrc , a and Vab ( DIA ) .
RESULTS	Participants had an FEV of 34.6 18 % predicted and a residual volume of 217.8 46.0 % predicted with significant chest wall asynchrony during quiet breathing at baseline ( RC , 31.3 38.4 ; and DIA , -38.7 36.3 ) .
RESULTS	Between-group difference in the change in RC and DIA during quiet breathing following treatment was 44.3 ( 95 % CI , -78 to -10.6 ; P = .003 ) and 34.5 ( 95 % CI , 1.4 to 67.5 ; P = .007 ) toward 0 ( representing perfect synchrony ) , respectively , favoring the LVR group .
RESULTS	Changes in RC and DIA were statistically significant on the treated but not the untreated sides .
CONCLUSIONS	Successful LVR significantly reduces chest wall asynchrony in patients with emphysema .

