 Chronic Obstructive Pulmonary Disease COPD is a common respiratory disease characterized by airflow limitation that is progressive and not fully reversible. Expiratory flow limitation EFL is the main mechanism leading to dynamic pulmonary hyperinflation DPH and intrinsic positive end-expiratory pressure PEEPi. DPH and PEEPi lead to increased inspiratory muscle efforts and impaired central drive mechanical and ventilation coupling, which is an important mechanism of dyspnea. Appropriate setting of extrinsic PEEP PEEPe can decrease inspiratory efforts and work of breathing, improve patient-ventilator synchrony in severe COPD patients with PEEPi and treated with mechanical ventilation. Nevertheless, the effects of CPAPPEEPe level on respiratory mechanics, especially on central drive mechanical and ventilation coupling, still need further investigations. 