Efficacy of Helium/Oxygen Compared to Air/Oxygen in Severe Exacerbation of Chronic Obstructive Pulmonary Disease (COPD) (ECHO/ICU)

• Duration of ICU stay and duration of index hospitalisation [ Time Frame: 10 days (average) ] [ Designated as safety issue: No ]
• Duration of invasive ventilation [ Time Frame: 10 days (average) ] [ Designated as safety issue: No ]
• Adverse events [ Time Frame: 6 months (post-randomization) ] [ Designated as safety issue: Yes ]
• Medico-economic parameters [ Time Frame: 6 months ] [ Designated as safety issue: No ]
  Overall costs and cost-effectiveness
• Physiological and laboratory parameters [ Time Frame: 10 days (average) ] [ Designated as safety issue: Yes ]
  Systolic and diastolic blood pressures, heart rate, central body temperature, arterial oxygen saturation, haematology and serum biochemistry
• Duration of NIV sessions [ Time Frame: 10 days (average) ] [ Designated as safety issue: No ]
  Cumulative daily duration of NIV sessions and their number during each of the 3-day treatment period and globally
• Time interval between the discharge of the index ICU stay and the first re-admission in ICU for severe exacerbation of COPD [ Time Frame: 6 months (post-randomization) ] [ Designated as safety issue: No ]

The primary objective of the study is to evaluate the efficacy of Helium/Oxygen (He/O2) 78%/22% compared to a conventional Air/O2 mixture in reducing endotracheal intubation rate and mortality in patients with severe hypercapnic exacerbations of Chronic Obstructive Pulmonary Disease (COPD) during their index Intensive/Intermediate Care Unit (ICU) stay.

Patients eligible for this study are critically ill patients with COPD admitted in Intensive Care Unit for an exacerbation of their chronic disease with hypercapnic acute respiratory failure. The patients will receive an Helium/Oxygen mixture or an Air/Oxygen mixture for a maximum of 72 hours during Non-Invasive Ventilation (NIV) and NIV-free sessions.

During NIV sessions, gas mixtures will be administered using a ventilator suitable for NIV with either He/O2 or Air/O2 and a NIV facemask.

Patients will be followed until hospital discharge and then contacted by phone up to the 6th month after randomization.

• Drug: Helium/Oxygen 78%/22%

  The Helium/Oxygen mixture will be administered during NIV and NIV-free sessions for a maximum of 72 hours using study dedicated devices.

  Patients will then receive the Air/Oxygen mixture with usual devices.

• Drug: Air/Oxygen

  The Helium/Oxygen mixture will be administered during NIV and NIV-free sessions for a maximum of 72 hours using study dedicated devices.

  Patients will then receive the Air/Oxygen mixture with usual devices.

• Experimental: Helium/Oxygen
  Helium/Oxygen will be administered for a maximum of 72 hours.
  Intervention: Drug: Helium/Oxygen 78%/22%
• Active Comparator: Air/Oxygen
  Air/Oxygen will be administered for a maximum of 72 hours.
  Intervention: Drug: Air/Oxygen

Inclusion Criteria:

• Patient with known or suspected COPD
• Patient presenting current exacerbation of COPD with hypercapnic acute respiratory failure
• Patient eligible for Non-Invasive Ventilation (NIV)
• Patient admitted in an ICU

Exclusion Criteria:

• Patient who had lung transplant
• Patient having a contraindication to NIV
• Patient with tracheostomy
• Patient requiring Oxygen flow rate > 6 L/min or Inspired Oxygen Fraction (FIO2) > 0.50
• Patient admitted in the ICU for more than 24 hours and/or having received NIV in ICU for more than 6 hours (in total) for the current exacerbation of COPD