Is There an Optimal Level of Positive Expiratory Pressure (PEP) to Improve Walking Tolerance in Patients With Severe COPD

Abstract Background The application of positive expiratory pressure (PEP) devices during exercise had been proposed in order to counteract the pulmonary hyperinflation, reduce the dyspnea and thus increase the exercise tolerance in patients with severe chronic obstructive pulmonary disease (COPD). This randomized controlled crossover trial investigated the effect of two different levels of PEP (1 cmH 2 O and 10 cmH 2 O) on distance covered at 6 min walk test (6MWT) in patients with severe COPD. Secondary outcomes were the evaluation of PEP effects on physiological and pulmonary function variables. Methods Seventy-two severe COPD patients, referred to our hospitals as in and out patients, were recruited. A basal 6MWT without devices was performed on the first day, and then repeated with PEP 1 cmH 2 O (PEP1) and 10 cmH 2 O (PEP10), with a randomized crossover design. Slow and forced spirometries, including the inspiratory capacity measure, were repeated before and after each 6MWT. Results 50 patients (average age 69.92 year, mean FEV 1 41.42% of predicted) concluded the trial. The 6MWT improved significantly among both PEP levels and baseline (323.8 mt at baseline vs 337.8 PEP1 and 341.8 PEP10; P P Conclusions In patients with severe COPD, the application of 1 cmH 2 O of PEP seems to improve the exercise tolerance as 10 cmH 2 O, with similar dyspnea. Further studies should investigate the effects of low levels of PEP on aerobic training programs.