EXERCISE PERFORMANCE AND GAS-EXCHANGE AFTER BILATERAL VIDEO-ASSISTED THORACOSCOPIC LUNG-VOLUME REDUCTION FOR SEVERE EMPHYSEMA

Lung volume reduction surgery (LVRS) improves: dyspnoea and pulmonary function in selected patients with severe emphysema. The purpose of th is study was to assess the effects of LVRS on exercise performance and gas exchange in relation to changes in pulmonary function. In 40 pati ents (63.2+/-1.4 yrs, mean+/-SE) with severe emphysema (forced expirat ory volume in one second (FEV1) 29+/-1% predicted, residual volume/tot al lung capacity (RV/TLC) ratio: 0.63+/-0.01) we assessed dyspnoea, pu lmonary function and exercise performance before and 3 months after bi lateral video-assisted thoracoscopic LVRS. The Medical Research Counci l dyspnoea score fell from 35+/-0.1 to 1.4+/-0.1 (p<0.0005); FEV1 incr eased by 55+/-9% to 44+/-2% pred (p<0.0005), RV/TLC decreased from 0.6 3+/-0.01 to 0.51+/-0.02 (p<0.0005). The diffusing capacity remained un changed. Maximal work load during bicycle ergometry increased from 34. 3+/-2.0 to 48.9+/-2.4 W (p< 0.0005), maximal oxygen uptake ((VO2)-O-1, max) from 10.0+/-0.4 to 12.8+/-0.3 mL.kg(-1).min(-1) (p<0.0005). The i ncrease in maximal ventilation during exercise ((VE)-E-1,max) from 29. 5+/-1.5 to 38.6+/-1.8 L.min(-1) (p<0.0005) was associated with increas es in tidal volumes at isowatt and maximal exercise while correspondin g breathing frequencies remained unaltered. The increases in (VO2)-O-1 ,max and (VE)-E-1,max correlated with the increases in FEV1 and the de creases in RV/TLC. We conclude that the improvement in pulmonary hyper inflation and airflow obstruction after bilateral thoracoscopic lung v olume reduction surgery may reduce ventilatory limitation, thereby inc reasing exercise capacity.