Correlation of unilateral thoracoscopic lung volume reduction with improvement in lung function and exercise performance in patients with severe pulmonary emphysema

This study was conducted to investigate the correlation of thoracoscopic lu ng volume reduction to changes in pulmonary function and exercise performan ce in patients with pulmonary emphysema, Unilateral thoracoscopic lung volu me reduction treatment was performed in 30 patients with severe pulmonary e mphysema. If large bullae mere present, they were excised using an endoscop ic stapling device, and the emphysematous pleura was contracted by neodymiu m:yttrium-aluminium-garnet laser to reduce the volume of nonfunctional lung air space. Pulmonary function and incremental exercise tests were performe d before and at least 3 months after treatment. Follow-up functional evalua tion showed a highly significant improvement in the forced expiratory volum e in Is (FEV1), forced vital capacity, static compliance, and maximal oxyge n uptake. The functional residual capacity as measured by the gas dilution method (FRCgas), was unchanged; however, it was found to be decreased signi ficantly when measured by body plethysmograph (FRCbox), Positive correlatio ns existed between the reduction in FRCbox and the increase in FEV1 (r = 0. 586, P = 0.0042) and maximal oxygen uptake (r = 0.550, P = 0.018). Pulmonar y ventilation and exercise ability in patients with pulmonary emphysema wer e improved in a volume-dependent manner by thoracoscopic lung volume reduct ion. These findings indicate that patients with a preoperative trapped gas volume level exceeding 11 would be ideal candidates for thoracoscopic lung volume reduction.