Preoperative evaluation of respiratory muscle strength, lung function and functional capacity of patients undergoing lung resection

Abstract

Introduction: Lung cancer can cause deterioration in lung function and functional capacity, impairing patient outcome after resection. Objective: To evaluate the respiratory muscle strength, lung function and functional capacity of patients in preoperative of lung resection for cancer, compared to normal values and staging. Methods: Patients of both genders were included aged 30–80 years with a diagnosis of lung cancer awaiting pulmonary resection surgery. Preoperative evaluation included measurement of respiratory muscle strength by manometer, lung function by spirometry and functional capacity through the sixminute walk test (6MWT). The values obtained were compared with predicted values obtained from equations proposed in the literature and compared the staging initial and advanced. Results: 59 patients with a mean age of 58.5±9.46 years were evaluated. There was a statistically significant difference between the obtained and the predicted values for maximum expiratory pressure (MEP): respectively 91 and 111.8 cmH2O, forced vital capacity (FVC): 3.14 and 4.08 L; forced expiratory volume in the first second (FEV1): 2.42 and 3.12 L; FEV1/FVC: 75 and 101%; and functional capacity: 453.9 and 562.9 m, in which the patients had lower values than those predicted by the literature, except FVC. There was no difference for inspiratory muscle strength (MIP: 110 and 102 cmH2O). Among the groups of patients only showed a difference of FVC (initial: 2.89; advanced: 3.41 L). Conclusion: Patients diagnosed with lung cancer in preoperative of resection, have impairments in expiratory muscle strength, lung function and functional capacity.