Study objectives: Little is known about long-term effects of pneumonectomy on lung function and exercise tolerance. We evaluated the long-term validity of two formulas frequently used to predict postoperative lung function, as well as trends in postoperative lung function and late postoperative exercise capacity.
Setting: Nonuniversity teaching hospital of Eindhoven, the Netherlands.
Patients: Patients who underwent pneumonectomy between 1993 and 1998 and survived for > 1 year after the operation.
Measurements and results: Lung function and exercise test data of 32 patients were analyzed. Postoperative FVC and FEV1 according to Kristersson/Olsen (split function of resected lung) and Juhl and Frost (number of segments to be resected) were calculated and compared with observed values measured in the third postoperative year. Calculated values correlated well with observed values, whereas Kristersson/Olsen appeared to be more accurate than Juhl and Frost. When considering trends in FEV1, we found a mean decline of 44 mL/yr; only three patients (12%) showed a rapid decline of > 100 mL/yr. Of 14 patients (44%), postoperative maximal exercise capacity was impaired due to ventilatory limitation.
Conclusions: The Kristersson/Olsen formula was more accurate in predicting postoperative lung function in the third postoperative year in pneumonectomy patients. Although the annual decline in FEV1 in these patients is almost the same as in healthy patients without COPD, pneumonectomy has serious implications on exercise capacity in many patients.