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

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

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.

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.

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