Evaluation of Non-invasive Pursed-lip Breathing Ventilation (PLBV) in Advanced COPD

Inclusion Criteria: 1. Signed informed consent 2. Age \>40 years 3. COPD diagnosis known for at least 12 months 4. NIV therapy for at least 3 months 4\. Regular use of NIV with extrapolated usage time of at least 700 hours / year 5. Current inspiratory NIV pressure ≥20 mbar 6. Patient understands the requirements of the study 7. Patient is able to follow the study protocol Exclusion Criteria: 1. Current COPD exacerbation (is allowed 4 weeks after end of treatment) 2. Radiologically proven pneumonia within the past month 3. Other leading pulmonary illness 4. Tracheostomy 5. Pneumothorax 6. Pregnancy or lactation 7. BMI \>35 kg/m² 8. Steroid therapy with \>15 mg prednisolon daily for \>1 month 9. Condition causing hypercapnia other than COPD 10. 6MWT distance of \>300 meters within the last 7 days 11. Previous therapy with the Vigaro NIV device 12. Weight loss of more than 5 kg / 12 months 13. Further criteria to exclude confounding factors