A Cochrane review included 11 studies with a total of 1 760 subjects. One study accounted for 68% of the participants recruited. Short-term 90 day mortality was significantly greater in all those who underwent lung volume reduction surgery (LVRS), but long-term mortality favoured surgery (table ). Participants with upper lobe-predominant emphysema and low baseline exercise capacity showed the most favourable outcomes related to mortality. Improvements in lung function, quality of life (SGRQ: St George's Respiratory Questionnaire) and exercise capacity were more likely with LVRS than with usual follow-up (table ).
| Outcome | Relative effect (95% CI) | Risk with control | Risk with intervention - surgery -(95% CI) | No of participants (studies) |
|---|---|---|---|---|
| Early mortality (90 days) | OR 6.16 (3.22 to 11.79) | 13 / 1000 | 77 / 1000 (42 to 138) | 1489 (5) |
| Long-term mortality (> 36 months) | OR 0.76 (0.61 to 0.95) | 547 / 1000 | 478 / 1000 (424 to 534) | 1280 (2) |
| Change in scores SGRQ (end of follow-up). A difference of 4 units is clinically important. The lower, the better | - | Mean SGRQ ranged from 57 units to 62.1 units | Mean SGRQ -13.78 units lower (-15.75 to -11.78) | 1326 (2) |
| Walking distance (end of follow-up): 6-minute walking distance | - | Range 303 to 350 metres | Mean walking distance 0.70 standard deviations higher (0.42 to 0.98) - equates 70 metres | 215 (5) |
| FEV1 (end of follow-up) | - | Range 0.64 L to 0.7L | Mean FEV1 0.2 L higher (0.13 to 0.28) | 188 (4) |