Purpose: Lung volume reduction surgery (LVRS) has been suggested as a therapy for emphysema. In evaluating patients for surgery, a major difficulty has been differentiating between asthma and emphysema. Methods: Twenty consecutive patients with severe COPD (FEV1 < 40%) were evaluated for possible LVRS. All patients underwent high resolution CT scan (HRCT), pulmonary function tests (PFTs) including body plethysmograph (BP), and subsequent pathologic correlation in some patients. Patients were scored independently for emphysema or asthma on the basis of their HRCT or PFTs. Hyperinflation (HI) was calculated as: (% predicted TLC+FRC+RV+RV/TLC)/4. Air trapping index (ATI) was: BP FRC - helium FRC. Reversibility was change in FEV1 with bronchodilators. Results: Of the 20 patients, 6 were felt to have mild to no emphysema seen on HRCT, 2 were felt to have fibrosis plus emphysema, 6 with bronchiectasis plus emphysema, and 6 with pure emphysema. All but one patient studied had hyperinflation (HI > 140%). There was poor correlation between HI or ATI and HRCT. The HRCT did correlate with patients for asthma (airway reversibility and normal DLCO). HRCT also identified 2 patients who had bronchiectasis as cause of severe hyperinflation and air trapping. Pathologic examination confirmed the presence of emphysema predicted by PFTs and HRCT. Conclusion: No single test could differentiate emphysema from asthma. However, the combination of bronchodilator studies, lung volumes, DLCO, and HRCT provided sufficient information to identify the emphysematous patient. Clinical Implication: Physiologic and radiologic assessment can be used to predict which patients may benefit from LVRS.
|Original language||English (US)|
|Issue number||4 SUPPL.|
|State||Published - Oct 1 1996|
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine
- Critical Care and Intensive Care Medicine
- Cardiology and Cardiovascular Medicine