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 diff erent chest wall compartments, which is a feature of emphysema, is not known.
METHODS: We used optoelectronic plethysmography to assess the eff ect of surgical and bronchoscopic
LVR on chest wall asynchrony. Twenty-six patients were assessed before and 3 months
aft er LVR (surgical [n 5 9] or bronchoscopic [n 5 7]) or a sham/unsuccessful bronchoscopic
treatment (control subjects, n 5 10). 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 ( u ) calculated for the asynchrony between Vrc,p and Vrc,a ( u RC),
and between Vrc,a and Vab ( u DIA).
RESULTS: Participants had an FEV 1 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
( u RC, 31.3° 38.4°; and u DIA, 2 38.7° 36.3°). Between-group diff erence in the change in u RC
and u DIA during quiet breathing following treatment was 44.3° (95% CI, 2 78 to 2 10.6;
P 5 .003) and 34.5° (95% CI, 1.4 to 67.5; P 5 .007) toward 0° (representing perfect synchrony),
respectively, favoring the LVR group. Changes in u RC and u DIA were statistically signifi cant
on the treated but not the untreated sides.
CONCLUSIONS: Successful LVR signifi cantly reduces chest wall asynchrony in patients with
emphysema. CHES