Negative pressure ventilation (NPV) is a non-invasive ventilation mode which provide better lung expansion. The major complication of NPV is decrease blood pressure and affects the hemodynamics. The effects of NPV on chronic obstructive pulmonary disease (COPD) patients with pulmonary rehabilitation program remains unknown.

Both of NPV or positive pressure ventilation (PPV) has impact of hemodynamics. NPV with cuirass ventilator increases venous return and leads to ventricular filling and increases cardiac output (CO); In contrast to NPV, the effect of PPV in most situations is a decreased venous return and leads to decreased CO. NPV improving ventilation and work of breathing in patients with chronic obstructive pulmonary disease (COPD).

Inclusion Criteria:

• Patients with COPD who received pulmonary rehabilitation program with NPV treatment

Exclusion Criteria:

• Recent exacerbation within 3-months
• Existing of tracheostomy
• Absence of NPV used
• Required of oxygen supplement during NPV
• Diagnosed of neuromuscular disease

COPD