A Study of Expiratory Pressure Modulation in Moderate to Severe COPD Patients - Phase 1b

A Study of Expiratory Pressure Modulation in Moderate to Severe COPD Patients - Phase 1b

Dynamic pulmonary hyperinflation (DH) and intrinsic positive end-expiratory pressure (PEEP) are well known problems in COPD patients with acute and chronic respiratory failure. Measurement of intrinsic PEEP level during both, invasive and non-invasive ventilation is of major importance since in some circumstances (e.g. during exercise or during exacerbations) it can significantly increase respiratory workload of COPD patients. Extrinsic PEEP applied during both, invasive and noninvasive ventilation is used to overcome intrinsic PEEP and therefore to avoid or reduce dynamic hyperinflation.

Inclusion Criteria:

1. Age > 18 years who are contractually capable and mentally able to understand and follow the instructions of the study personnel
2. Signed informed consent
3. Moderate to severe COPD patients (FEV1/FVC ratio <70% and FEV1 < 50% pred) with chronic hypercapnic respiratory failure (PaCO2 >45 mmHg)
4. Currently using NIV

Exclusion Criteria:

1. Acute exacerbation of COPD, acute respiratory failure (ph < 7,35 and/or respiratory rate >30/min)
2. Unstable heart failure
3. Cardiac failure with dehydration
4. Pregnancy/breastfeeding women
5. Pneumothorax/-mediastinum
6. Increased risk of pneumothorax, pneumomediastinum or venous air embolism
7. In the opinion of the investigator, the patient is unsuitable for the study