[en] Long-acting bronchodilators are recommended as a first-line treatment for chronic obstructive pulmonary disease (COPD), although their effects for postoperative lung cancer patients with COPD are still not well known. A prospective randomized trial was used to examine the efficacy of bronchodilators on postoperative pulmonary function and quality of life (QOL). Twenty lung cancer patients with COPD who had lobectomies were randomized. A control group (n=10) did not receive bronchodilators. An experimental group (n=10) received tiotropium and salmeterol. Patients were divided into two COPD grades: stage I COPD and stage II-III COPD. Results for pulmonary function, 6-minute walking test, and the St. George's Respiratory Questionnaire (SGRQ) were compared. Diaphragmatic motion on dynamic magnetic resonance imaging was also analyzed. The patient demographics were similar in the two groups. Except for pulmonary function results at 2 weeks, no other parameters were significantly different. However, in stage II-III COPD, forced expiratory volume in 1 second, forced vital capacity, inspiratory capacity, the total score of the SGRQ, and diaphragmatic motion in the experimental group (n=5) were significantly better than those in the control group (n=4) at various time points (all P<0.05). The daily inhalation of bronchodilators was effective for maintaining the respiratory function and QOL in lung cancer patients with moderate to severe COPD. (author)