Selection criteria for valve therapy in emphysema
| Severe airflow obstruction: FEV1 between 15% and 45% of predicted |
| Severe air trapping and hyperinflation: TLC > 100% and RV > 175% of predicted |
| Severe emphysematous destruction in target lobe: > 50% involvement |
| Absence of collateral ventilation between target lobe and neighboring lobe or lobes |
| Adequate gas exchange: diffusion capacity > 20% of predicted, PaCO2 < 50 mm Hg, PaO2 > 45 mm Hg at baseline |
| No history of frequent severe exacerbations: > 2 hospitalizations over the past year |
| Absence of clinically significant sputum production: “significant” production, > 4 tablespoons per day |
| No significant comorbidities: eg, cor pulmonale, ejection fraction < 45%, recent myocardial infarction |
| No prior lung volume reduction surgery, lobectomy, lung transplant |
FEV1 = forced expiratory volume in 1 second; PaCO2 = partial arterial pressure of carbon dioxide; PaO2 = partial arterial pressure of oxygen; RV = residual volume;
TLC = total lung capacity
Adapted from reference 23.