Lung MORphological Modifications Evaluated by Electrical Impedance Tomography During Preoxygenation for the Intubation of Hypoxemic Patients: Comparison of Standard Oxygenation, High Flow Nasal Oxygen Therapy, and NonInvasive Ventilation (MORPHEIT Study, an Ancillary Study of PREONIV Trial)

Lung MORphological Modifications Evaluated by Electrical Impedance Tomography During Preoxygenation for the Intubation of Hypoxemic Patients: Comparison of Standard Oxygenation, High Flow Nasal Oxygen Therapy, and NonInvasive Ventilation (MORPHEIT Study, an Ancillary Study of PREONIV Trial)

Prospective, randomized clinical multicentric study, in ICU, during preoxygenation for the intubation of hypoxemic patients.

Electrical impedance tomographic evaluation of lung morphology variations according to the preoxygenation technique : Comparison of Standard Oxygenation, High Flow Nasal Oxygen Therapy, and NonInvasive Ventilation

Preoxygenation before endotracheal intubation in the ICU is a prerequisite to limit complications, ranging from desaturation, severe hypoxemia and bradycardia with potential cardiac arrest and death. International recommendations suggest the use of non-invasive ventilation (NIV) technique whenever possible. High flow nasal cannula (HFNC) has recently gained growing interest in the ICU as a treatment of acute respiratory failure, to improve extubation success and as a preoxygenation device before endotracheal intubation. Conflicting results have been published.

The PREONIV study was designed to compare NIV, HFNC and conventional preoxygenation with valve bag mask for the preoxygenation before endotracheal intubation.

Investigator propose to add a lung morphology analysis during preoxygenation. Electrical impedance tomography (EIT) is a non invasive tool which analyse lung aeration variations via the evolution of local thoracic impedances with electrical loop circulating around a thoracic belt with electrodes.

The hypothesis is that the technique of preoxygenation might correlate with oxygen desaturation and potential intubation related complications (PREONIV study). Moreover lung morphology modifications evaluated by EIT might be associated with the preoxygenation technique (MORPHEIT study).

Investigator wish to asses lung morphological modifications evaluated by EIT during preoxygenation in a prospective non blinded randomized fashion.

Inclusion Criteria:

• • adults patients

  • requiring intubation and hypoxemia (defined by PaO2/FiO2 below 200)
  • patient covered by french health care system
  • patient included in Hopital Estaing, Clermont-Ferrand

Exclusion Criteria:

• • patient refusal

  • intubation for other causes (excluding hypoxemia)
  • impossibility to measure pulse oxymetry value
  • contraindication for NIV : vomiting
  • NIV intolerance
  • cardiac arrest during intubation