ABSTRACT
Background: chronic obstructive pulmonary disease [COPD] increases tissue compliance, reduces elastic recoil on expiration and limits expiratory air flow which increases residual volume [RV] and thoracic gas volume [TGV] resulting in lung hyperinflation and air trapping
Objective: to evaluate pulmonary function changes after long acting inhaled bronchodilators and breathing exercise for 2 months in stable COPD patients
Study design and intervention: randomized controlled study included 60 hyperinflated stable COPD patients [total lung capacity >120% predicted].Patients were classified into 4 groups [15 patient in each group]: Breathing exercise group, Salmeterol inhalation group, Tiotropium bromide inhalation group and Control group
Main outcome measures: dyspnea and pulmonary function tests[PFT] parameters
Results: in Breathing exercise group, the mean forced expiratory volume in 1 second [FEV l], forced vital capacity [FVC] and inspiratory capacity[1C] increased significantly [pi 0.005 for each], the mean functional residual capacity [FRC], RV and total lung capacity [TLC] decreased significantly [PO 0.005 for each]. In Salmeterol inhalation group the mean FEVl and the FEVl/FVC % predicted increased significantly [p=0.014, p=0.040 respectively], the mean FRC, RV, TLC, and RV/TLC % predicted decreased significantly [p 0.005 for each]. In Tiotropium bromide inhalation group the mean FEVl value and mean IC increased significantly [p=0.001, p=0.022 respectively], the mean value for RV/TLC actual and the mean value for RV/TLC % of predicted significantly increased [p 0.005 for each]
Conclusions: in COPD addition of inhaled long acting bronchodilator or breathing exercise reduce hyperinflation and gas trapping in patients with significant hyperinflation, often to a remarkable degree