Effects of Positive Expiratory Pressure Breathing During Exercise in Patients With COPD

Effects of Expiratory Positive Airway Pressure on Exercise Tolerance, Dynamic Hyperinflation, and Dyspnea in COPD

“…The reduction in exercise lung volumes appear, in fact, to be secondary to a significant constraint to V T and, without a compensatory increase in breathing frequency, lead to VE remaining lower than expected during exercise as previously described. 20 This can explain a similar dyspnea observed in the present and previous study 17 or even worse dyspnea 22 during exercise, regardless of a significant improvement in important indexes of lung hyperinflation. 33 It means that constraints to V T increases continued to happen with exercise progression.…”

“…These are probably be related to the induction of The supposed advantage of applying pressure support only during expiration, ie, to attenuate dynamic airway compression and reduce lung hyperinflation (and elastic work of breathing), 10 -12 seemed to be counterbalanced by increases in expiratory muscle effort (and resistive working of breathing) during exercise. 20,31 Moreover, because we continuously monitored ventilatory and metabolic parameters during exercise, we used a device (Fig. 1) that allowed measurements of those parameters by a computerbased system while simultaneously applying the pressure in the expiratory outlet.…”

“…13 It has been effective in reducing dynamic hyperinflation 14,15,16 and post-exercise dyspnea, 17 as well as improving exercise capacity. 14,18,19 On the other hand, EPAP can increase the work of breathing 20 and decrease venous return, 21 which could partially explain the deleterious effect on exercise endurance recently described. 16,22 Cardiopulmonary exercise testing (CPET) has proven useful in establishing the link between exercise performance and mechanisms of limitation as well as in determining which interventions can improve this relationship.…”

Effects of Nasal Positive Expiratory Pressure on Dynamic Hyperinflation and 6-Minute Walk Test in Patients With COPD

“…The underlying mechanism that is considered to provoke the reduction in dynamic hyperinflation is the diminution of airway compression. 2,14,43 In patients with emphysema the equal pressure point is moved more peripherally, resulting in earlier airway compression during expiration particularly at high flow rates, which leads to hyperinflation. 1 Similar to the effect of pursed lip breathing, expiratory airway resistance increases intraluminal airway pressure resulting in a shift of the equal pressure point back to central airways, which counteracts early airway collapse.…”

“…8 There has also been longstanding interest in the effect of positive expiratory pressure (PEP) breathing in COPD patients, in whom it is thought to produce a reduction of breathing frequency, improved gas exchange, as well as less airway collapse and air-trapping. 2,14 It is considered to have similarities to pursed lip breathing, a breathing maneuver that is spontaneously adopted by some patients with COPD and is routinely taught as a breathing technique in respiratory physiotherapy. 15,16 Currently, PEP is often used in pulmonary rehabilitation as a breathing exercise, especially in terms of assistance in the removal of secretions, and can be applied by several techniques, including pursed lip breathing, blow bottle technique, oral high-frequency oscillators, and PEP devices.…”