High Flow Nasal Cannula Therapy for Early Management of Acute Hypercapnic Cardiogenic Pulmonary Edema in the Emergency Department

Study Overview
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Brief Summary
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High flow nasal therapy (HFNT) has not been well evaluated for treating hypercapnia The purpose of this study is to determine whether high flow nasal therapy (HFNT) can decrease hypercapnia and improve respiratory distress parameters in Emergency Department patients with acute hypercapnic respiratory failure related to cardiogenic pulmonary edema and to compare its efficacy to that of non invasive ventilation.

Detailed Description
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This is a prospective observational study conducted as a preliminary study to the randomized controlled OPTICAP trial (NCT02874339). Prospective observational exploratory study including ED patients with a suspected diagnosis of acute hypercapnic respiratory failure related to cardiogenic pulmonary edema who require NIV according to the joint recommendations from the French society of anaesthesia and intensive care and the French society for intensive care. Patients will receive a 1hr treatment session by either NIV or HFNT, depending on the attending ED physician expertise in using HFNT Repeat evaluation of arterial blood gases and respiratory parameters and dyspnea will be performed before and after treatment sessions according to current guidelines. Improvement in PaCO2 and other respiratory parameters after 1hr treatment by HFNT will be analysed and compared to that of NIV.

Official Title
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High-flow Nasal Therapy for Early Management of Hypercapnic Respiratory Failure Due to Acute Cardiogenic Pulmonary Edema in the ED: a Prospective Observational Study

Conditions
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Acute Cardiogenic Pulmonary Edema, Hypercapnic Respiratory Failure

Intervention / Treatment
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* Device: High flow nasal therapy (HFNT) : Optiflow™
* Device: Non invasive ventilation (niv)


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: a suspected diagnosis of acute cardiogenic pulmonary edema presenting with any of the following criteria: dyspnea (orthopnea or a worsening of dyspnea according to NYHA criteria) respiratory rate >20 b/min bilateral crepitant rales at pulmonary auscultation pulmonary infiltrate on chest X-ray signs of respiratory failure or any of the following clinical, laboratory or radiology signs: Use of accessory respiratory muscles or paradoxical abdominal movement Cardiomegaly (cardiothoracic ratio >0.5) Hypertensive crisis PaO2/FiO2 ≤ 300 mmHg breathing O2> 8L/min or PaO2 ≤ 63mmHg breathing room air hypercapnia (PaCO2>45 mmHg at arterial blood gas analysis) Exclusion criteria: acute exacerbation of chronic obstructive pulmonary disease or associated dyspnea from non cardiac origin Fever (>38,5°), sepsis or ongoing infection Contra-indication to NIV

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 |
| --- | --- |
| Optiflow tm<br>High flow nasal therapy (HFNT) | Device: High flow nasal therapy (HFNT) : Optiflow™<br>* HFNT will be administered through a heated humidifier (Airvo 2, Fisher and Paykel healthcare) and applied through large bore binasal prongs. Initial gas flow rate will be set at of 60 l/min and adjusted to 40-50 l/min based on patient's tolerance. FiO2 will be adjusted to maintain an SpO2 ≥ 92%. Initial temperature will be set at 37° and reduced according to patient's tolerance<br>* Other names: Optiflow™;|
| Non invasive ventilation (NIV)<br>Non invasive ventilation (NIV) | Device: Non invasive ventilation (niv)<br>* NIV will be delivered through a face mask connected to a dedicated ventilator with pressure support applied in a noninvasive ventilation mode (Monnal T75, Airliquide Medical Systems, Antony, France). The Pressure-support level will be adjusted to obtain an expired tidal volume of 6-8 ml/kg of predicted body weight and a respiratory rate of 25-30 b/min. PEEP (range 5-10 cm of water) and FiO2 will be adjusted to maintain an SpO2 ≥92% and to patient's comfort.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in PaCO2 after a 1-hour treatment session | PaCO2 will be measured from standard laboratory arterial blood gas analysis performed at the end of the first 1-hour-treatment session | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood gas (PaO2, pH, SaO2) | blood gas (PaO2, pH, SaO2) measured from standard laboratory arterial blood gas analysis at the end of each 1h-ventilatory support session and throughout ventilatory support | at 1 hour | 
| Respiratory rate | Respiratory rate, measured over 1-min as part of standard clinical assessment after each 1h ventilatory support session and throughout ventilatory support | at 1 hour | 
| signs of increased work of breathing | signs of increased work of breathing assessed based on patient's use of accessory respiratory muscles and paradoxical abdominal movement and measured using 5-point likert scales ranging from 1 to 5. Signs of increased work of berthing will be assessed at the end of each 1h ventilatory support sessions throughout ventilatory support | at 1 hour | 
| Dyspnea | Dyspnea recorded by the patient using a Modified Borg scale ranging from 0 to 10. Dyspnea will be measured at the end of each 1h ventilatory support sessions and throughout ventilatory support | at 1 hour | 
| comfort | Comfort recorded by the patient using a visual analog scale from 0 to 10. Comfort will be assessed at the end of each 1h ventilatory support sessions and throughout ventilatory support | at 1 hour | 
| Proportion of patients | Proportion of patients with a normalized PaCO2 (PaCO2 equal or lower than 45 mmHg), | at 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Acute cardiogenic pulmonary, Respiratory failure, Hypercapnia, High flow nasal oxygen, Non invasive ventilation, Emergency department