The superiority of exercise testing over spirometry in the evaluation of postoperative lung function for patients with pulmonary disease

Thoracic surgeons have often been embarrassed by the discrepancy between an improvement in symptoms and the unchanged or even worse results of spirometry in postoperative patients with either bullae or inflammatory lung disease. Forty-four patients with lung diseases, who underwent a total of 47 operations, were categorized as follows: 12 cases of empyema, 16 cases of giant bulla (undergoing surgery a total of 19 times), 4 cases of bronchiectasis, and 12 cases of other miscellaneous diseases. All patients were tested preoperatively and again 4–6 months after surgery on both the spirometer and treadmill exercise tests. The forced vital capacity (FVC) and forced expiratory volume (FEV_1.0) results were as follows: the empyema group 1.82±0.52 liters preoperatively to 1.93±0.69 liters postoperatively and 1.47±0.44 liters to 1.56±0.53 liters, respectively; and the giant bulla group, 3.49±0.96 liters to 3.35±0.77 liters and 2.35±0.96 liters to 2.48±0.69 liters, respectively. However, the exercise time was prolonged in the empyema group from 6.00±3.77 min to 8.33±3.80 min (P<0.01) and in the giant bulla group from 11.83±3.71 min to 12.92±2.84 min (P<0.05). It was thus concluded that exercise testing should be chosen for the postoperative evaluation of patients with inflammatory pulmonary disease and giant bullae, especially if any discrepancies are seen between spirometry and performance status, because on the basis of our results, it appears that the benefits obtained by surgery are best measured by the dynamic values of exercise testing and not by the static values of spirometry at rest.