Lung function after bilateral lower lobe lung volume reduction surgery for α 1 ‐antitrypsin emphysema

This study explores the mechanism(s) of airflow limitation following lung volume reduction surgery (LVRS) in patients with emphysema due to homozygous α 1 ‐antitrypsin (AT) deficiency. Bilateral targeted lower lobe stapled LVRS using video thoracoscopy was performed in six patients (five males) aged 61±9 yrs (mean± sd ) with α 1 ‐AT emphysema. Two patients received only a 6‐month follow‐up. However, four patients, at 22, 24, 27 and 36 months post‐LVRS, noted relief from dyspnoea and increased walk tolerance. At 27±6 months (mean± sd ) post‐LVRS, their forced expiratory volume in one second improved only from 30±2% of the predicted value (mean± sem ) before surgery to 33±1% pred after surgery. Yet, total lung capacity (TLC) decreased from 151±13 to 127±10% pred; diffusing capacity increased from 35±9 to 59±9% pred; and vital capacity increased from 68±10 to 88±5% pred. In three patients, static lung elastic recoil at TLC increased from 1.1±0.15 to 1.2±0.10 kPa. Using flow/pressure curves, the mechanism for expiratory airflow limitation pre‐LVRS and the improvement noted post‐LVRS could be primarily accounted for by the initial loss and subsequent increase in lung elastic recoil. Bilateral lung volume reduction surgery provides modest physiologic improvement for 2–3 yrs in patients with α 1 ‐antitrypsin emphysema due to increases in lung elastic recoil.