Conduct of Nasal High Flow Oxygen in Acute Respiratory Failure

Study Overview
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Brief Summary
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Although many studies have investigated the clinical benefits of nasal high flow during acute hypoxemic respiratory failure, there is no data (and even less so recommendations) on how to best conduct this technique, including its initiation and its weaning periods. Investigators will assess in a multicenter, observational study, the way clinicians use nasal high flow therapy in patients with acute respiratory failure in order to try identify one or more strategies that may be then compared in an interventional study.

Detailed Description
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Nasal high flow oxygen therapy is increasingly used as a first-line treatment for hypoxemic acute respiratory failure, because of its remarkable tolerance (in comparison with NIV) and its physiological effects (nasopharyngeal dead space washout, positive end-expiratory pressure effect with possible alveolar recruitment, better matching with the patient's inspiratory flow, more reliable and adjustable FiO2); that together contribute to a reduction in respiratory workload and better oxygenation. Although many studies have investigated the clinical benefits of nasal high flow during acute hypoxemic respiratory failure, there are no data (and even less recommendations) on how to best conduct this technique, including its initiation and its weaning periods. Because different approaches exist among clinicians, investigators believe that a multicenter observational study that would collect data regarding the different ways high flow is conducted in patients with acute respiratory failure is necessary before performing an interventional study that would test and compare different strategies in order to answer the question: what are the best strategies (in terms of flow and FiO2 settings) to initiate and to wean high-flow oxygen therapy in patients with acute respiratory failure? Investigators will assess in a multicenter, observational study, the way clinicians use nasal high flow therapy in patients with acute respiratory failure in order to try identify one or more strategies that may be then compared in an interventional study.

Official Title
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Conduct of High Flow Nasal Cannula Oxygen During Acute Hypoxemic Respiratory Failure: a Multicentre Observational Study

Conditions
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Hypoxemia, Acute Respiratory Failure With Hypoxia

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged 18 or older admitted to the intensive care unit (ICU) or to the intermediate care for acute hypoxemic respiratory failure (whatever the cause) treated with nasal high flow oxygen therapy with a minimal FiO2 of FiO2≥50% and a gas flow ≥40 L/min anticipated duration of nasal high flow therapy greater or equal to 24 hours Non-inclusion Criteria: prophylactic, post-extubation nasal high flow therapy palliative nasal high flow therapy (do-not-resuscitate order) Exclusion criteria - nasal high flow therapy administered for less than 24 hours

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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| values of gas flow over time (in liters per minute) | values of gas flow set on the device of nasal high flow will be monitored over time so as to describe how physicians set and modify this parameter during treatment with nasal high flow | entire duration of high flow therapy (5 to 7 days) | 
| values of fraction in inspired oxygen (FiO2) over time (between 0.21 and 1.0) | values of FiO2 set on the device of nasal high flow will be monitored over time so as to describe how physicians set and modify this parameter during treatment with nasal high flow | entire duration of high flow therapy (5 to 7 days) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| respiratory rate (breath per minute) | values of respiratory rate upon initiation of nasal high flow and at each change of nasal high flow parameters (gas flow or FiO2) will be monitored. | entire duration of high flow therapy (5 to 7 days) | 
| pulse oximetry (SpO2) (percentage) | values of oxgen saturation upon initiation of nasal high flow and at each change of nasal high flow parameters (gas flow or FiO2) will be monitored. | entire duration of high flow therapy (5 to 7 days) | 
| values of the Respiratory rate Oxygenation indeX (ROX) index defined as the ratio of pulse oximetry over fraction of inspired oxygen to respiratory rate | values of the ROX index will be monitored at different time points (2, 6 and 12 hours after nasal high flow therapy initiation) | 12 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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high flow nasal oxygen, acute hypoxemic respiratory failure, adults, intensive care unit