High-flow Oxygen Therapy vs Non-invasive Ventilation: Comparison of Alveolar Recruitment in Acute Respiratory Failure

Study Overview
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Brief Summary
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This physiological study showed an increase in regional ventilation with NIV but no difference in alveolar recruitment as compared to HFNC in patients with hypoxemic ARF. Although NIV provided better oxygenation than HFNC, the effect on lung volumes could explain the potentially deleterious effect of NIV in hypoxemic ARF, reinforcing the recently developed concept of patient self-inflicted lung injury.

Detailed Description
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Background: High-flow nasal cannula (HFNC) oxygen therapy has recently shown clinical benefits in hypoxemic acute respiratory failure (ARF) patients, while the interest of non-invasive ventilation (NIV) remains debated. The primary endpoint was to compare alveolar recruitment using global end-expiratory electrical lung impedance (EELI) between HFNC and NIV. Secondary endpoints compared regional EELI, lung volumes (global and regional tidal volume variation (TV)), respiratory parameters, hemodynamic tolerance, dyspnea and patient comfort between HFNC and NIV, relative to face mask (FM).

Official Title
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High-flow Oxygen Therapy Versus Non-invasive Ventilation: a Randomised Physiological Cross-over Study of Alveolar Recruitment in Acute Respiratory Failure

Conditions
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Acute Respiratory Failure With Hypoxia

Intervention / Treatment
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* Device: non invasive ventilation and high flow nasal canulae oxygen therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients referred in ICU with hypoxemic acute respiratory failure due to a community acquired pneumonia confirmed by chest X ray, with PaO2 < 60mmHg in ambient air, without hypercapnia (PaCO2 < 45 mmHg), requiring more than 6L/min of O2 on admission with high concentration FM, and justifying HFNC or NIV for the attending ICU physician Exclusion Criteria: cardiogenic pulmonary oedema, moderate to severe underlying respiratory disease including COPD (chronic obstructive pulmonary disease) contraindication to or failure of previous NIV or HFNC with the need for immediate invasive ventilation pregnant or breast-feeding women carrier of an implantable defibrillator or pacemaker body mass index (BMI)>50 kg/m2 with cutaneous lesion next to the positioning zone of the Pulmovista® (Dräger, Lübeck, Germany) belt

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| NIV/HFNC<br>patients receiving non-invasive ventilation than high flow nasal canulae oxygen therapy | Device: non invasive ventilation and high flow nasal canulae oxygen therapy<br>* patients with hypoxemic acute respiratory failure received alternatively non invasive ventilation and high flow nasal canulae oxygen therapy<br>|
| HFNC/NIV<br>patients receiving high flow nasal canulae oxygen therapy than non-invasive ventilation | Device: non invasive ventilation and high flow nasal canulae oxygen therapy<br>* patients with hypoxemic acute respiratory failure received alternatively non invasive ventilation and high flow nasal canulae oxygen therapy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| global EELI | measurement of global end respiratory lung impedance with non invasive ventilation vs with high flow nasal canulae oxygen therapy, standard unit | after 5 minutes of stable breathing with the oxygenation technic | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ROI EELI | measurement of regional of interest (ROI) end respiratory lung impedance with non invasive ventilation vs with high flow nasal canulae oxygen therapy, standard unit | after 5 minutes of stable breathing with the oxygenation technic | 
| global TV | measurement of global tidal variation (TV) with non invasive ventilation vs with high flow nasal canulae oxygen therapy, standard unit | after 5 minutes of stable breathing with the oxygenation technic | 
| ROI TV | measurement of regional tidal variation with non invasive ventilation vs with high flow nasal canulae oxygen therapy, standard unit | after 5 minutes of stable breathing with the oxygenation technic | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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alveolar recruitment, electrical impedance tomography, non-invasive ventilation, high-flow nasal cannula oxygen therapy, hypoxemic acute respiratory failure