Efficacy of High-intensity NPPV and Low-intensity NPPV in Patients With Chronic Hypercapnic COPD
Efficacy of High-intensity NPPV and Low-intensity NPPV in Patients With Chronic Hypercapnic COPD
High-intensity noninvasive positive pressure ventilation (NPPV), which can well improve the
 gas exchange and reduce the work of breathing of patients, is a new strategy targeted at
 maximally reducing arterial carbon dioxide. However, no definitive conclusions have been
 drawn to decide whether high-intensity NPPV is the best setting for treating patients with
 chronic hypercapnic COPD. For now, no unified method for setting up high-pressure NPPV has
 been established. Most of the trials utilized gradually increased inspiratory positive airway
 pressure depending on the patient's tolerance. However, from a respiratory physiology point
 of view, excessive inspiratory positive airway pressure may lead to lung hyperinflation,
 increased intrinsic positive end expiratory pressures, increased oxygen consumption, and
 ineffective work of breathing.Therefore, seeking a method to establish individualized
 high-intensity NPPV is of vital importance.
Inclusion Criteria:

 Clinically stable with chronic hypercapnic COPD (baseline arterial carbon dioxide pressure
 (PaCO2) of 50 mmHg or higher, measured resting in a sitting position and breathing room air
 without having used NPPV for at least 1 hour)

 Exclusion Criteria:

 -  other lung/pleural diseases or thoracic deformity

 -  severe heart failure (New York Heart Association class IV), severe dysrhythmia

 -  unstable angina, or malignant comorbidity

 -  obesity (BMI ≥ 35 kg/m²)

 -  severe obstructive sleep apnea syndrome