Introduction Chronic obstructive pulmonary disease (COPD) is a common condition and the fourth leading cause of death worldwide. With the rise of non-invasive ventilation (NIV), mortality among patients admitted for acute hypercapnic respiratory failure has decreased, though to a lesser extent than reported in the studies that validated this technique. We hypothesize that inappropriate initial ventilatory parameter settings for NIV could be associated with increased morbidity and mortality in this context.

Objective The primary objective of this study is to assess the initial NIV settings used in intensive care units (ICUs) and respiratory intensive care or medical intensive care units (MICUs) in this patient population. A secondary objective is to evaluate whether specific ventilatory settings are associated with mortality or the need for invasive mechanical ventilation (IMV).

Methods This is a prospective multicenter observational study aiming to include 976 patients. NIV settings will be recorded at initiation, after the first recommended arterial blood gas (ABG) evaluation (between 1.5 and 2 hours of ventilation), and at 24 and 48 hours. Patient characteristics, including medical history, clinical and biological parameters at admission, will be collected. Vital status and the need for IMV will be recorded at ICU discharge and on day 28 (D28).

Inclusion Criteria:

• Adult COPD Patient
• Known or suspected COPD diagnosis as assessed by the attending physicians
• Admitted to a medical intensive care unit (MICU), respiratory intensive care unit, or MICU
• Hypercapnic respiratory distress
• NIV indication determined by the physician
• Covered by social security

Exclusion Criteria:

• Pregnant or breastfeeding women
• Other obstructive diseases (asthma, bronchiectasis, cystic fibrosis, bronchiolitis, pulmonary fibrosis, restrictive thoracic syndrome) Central hypoventilation (Ondine's syndrome, iatrogenic), neurological (neuromuscular disease), osteoarticular (kyphoscoliosis), or ENT-related causes
• Immediate need for intubation
• Acute pulmonary edema
• Contraindications to NIV (untreated pneumothorax, shock, cardiac arrest, uncontrolled vomiting, upper gastrointestinal bleeding, cervicofacial trauma, coma except when related to hypercapnia)
• Patients under legal guardianship
• Incarcerated individuals

COPD Patients Admitted to Critical Care for Hypercapnic Respiratory Distress