Nasal High Flow Versus Non-invasive Ventilation for Early Treatment of Acute Exacerbation of Chronic Obstructive Pulmonary Disease With Hypercapnic Acidosis

Study Overview
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Brief Summary
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The purpose of this study is to determine whether nasal high flow is non inferior to non invasive ventilation (NIV) in the early treatment of patients with acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) and hypercapnic acidosis in the emergency department (ED). After obtaining informed consent, participants will be randomly assigned to receive either nasal high flow or non invasive ventilation (NIV, reference treatment) as respiratory support. Researchers will compare both respiratory support groups to see if their blood gas analysis and respiration return to normal ranges.

Detailed Description
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Prospective multicenter comparative therapeutic study, with a randomized controlled parallel and open design. Nasal high flow will be compared to NIV (reference treatment) for early treatment of AE-COPD associated with hypercapnic acidosis. Adult patients admitted to the ED for AE-COPD with hypercapnic acidosis will be randomized to receive either nasal high flow or NIV as ventilatory support. Ventilatory support will be applied in 2h sessions and resumed as needed according to international guidelines for NIV treatment. Close monitoring of clinical and gas parameters will be conducted with repeat assessment and serial blood gas testing at 2h and after each 2h session of respiratory support in the ED (2h, 4h, 6h) and at 24h. Standard oxygen therapy will be administered as required between ventilatory support sessions to maintain a target peripheral oxygen saturation (SpO2 : 88-92%). Patient's dyspnea and comfort will be assessed before treatment and at 2h, and after each respiratory support session in the ED Patients will receive standard medical treatment for AE-COPD (bronchodilator, corticosteroids and antibiotics) according to current practice and 2023 global initiative guidelines for the management of COPD (GOLD). Patients will be followed up at day 28 by means of medical records review and telephone interview

Official Title
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Nasal High Flow in Early Management of Patients Admitted to the Emergency Department for Acute Exacerbation of Chronic Obstructive Pulmonary Disease With Hypercapnic Acidosis : a Randomized Controlled Non Inferiority Study

Conditions
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Acute Exacerbation of Chronic Obstructive Pulmonary Disease, Hypercapnic Acidosis, Respiratory Failure With Hypercapnia

Intervention / Treatment
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* Device: Ventilatory support via nasal high flow
* Device: Ventilatory support via NIV


Participation Criteria
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Eligibility Criteria
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Adult Patient admitted to the ED for acute exacerbation of COPD (AE-COPD)and respiratory acidosis (PaCO2 > 45 mmHg and pH <7.35), for whom ventilatory assistance by NIV is indicated (SPLF 2017, GOLD2023 recommendations) Inclusion Criteria: Patients with ability to understand and give an informed consent Patients affiliated with or who benefit from a social security Patients admitted to the emergency department for a clinical suspicion of AE-COPD based on clinical history, physical examination and chest X-ray (SPLF 2017) Patients with acute respiratory failure defined by: Respiratory rate ≥ 25 bpm AND/OR Signs of respiratory failure (use of accessory respiratory muscles, paradoxical abdominal movement) Patients with respiratory acidosis defined by PaCO2 > 45 mmHg AND pH < 7.35 (measured on arterial blood gas) Exclusion Criteria: Patients who have already received NIV treatment before inclusion (including in-hospital or prehospital, with the exception of NIV at home) Contraindication to non-invasive ventilation (SPLF 2017 and GOLD 2023 recommendations) Patient uncooperative, agitated, opponent of the technique

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants are randomly assigned to either one of two groups of respiratory support (NIV or nasal high flow) in parallel. Randomization will be in a 1:1 ratio, and stratified by center, severity of hypercapnia and acidosis
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Nasal high flow<br>Nasal high flow will be administered through a heated humidifier (Airvo 3, Fisher and Paykel healthcare) and applied through large bore binasal prongs. Initial gas flow rate will be set at 60 l/min, FiO2 will be adjusted to maintain an SpO2 88-92% and Initial temperature will be set at 37° and reduced according to patient's tolerance. Ventilatory support will be applied in 2h sessions and resumed as needed according to international guidelines for NIV treatment | Device: Ventilatory support via nasal high flow<br>* Ventilatory support will be applied in 2h sessions and resumed as needed according to international guidelines for NIV treatment.<br>|
| Active Comparator: Non invasive ventilation<br>NIV will be delivered through a face mask connected to a ventilator with pressure support applied in a noninvasive ventilation mode. 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 88-92% and to patient's comfort. Ventilatory support will be applied in 2h sessions and resumed as needed according to international guidelines for NIV treatment. | Device: Ventilatory support via NIV<br>* Ventilatory support will be applied in 2h sessions and resumed as needed according to international guidelines for NIV treatment.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in PaCO2 | PaCO2 will be measured from standard laboratory arterial blood gas analysis before the initiation of ventilatory assistance and after 2 hours of treatment | 2 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in pH | Blood gas parameters will be measured from standard laboratory arterial blood gas analysis before the initiation of ventilatory support and after 2 hours of treatment | 2 hours | 
| Change in PaO2 | Blood gas parameters will be measured from standard laboratory arterial blood gas analysis before the initiation of ventilatory support and after 2 hours of treatment | 2 hours | 
| Change in PaCO2 | Blood gas parameters will be measured from standard laboratory arterial blood gas analysis before the initiation of ventilatory support and after sessions of ventilatory support | up to 24 hours | 
| Change in pH | Blood gas parameters will be measured from standard laboratory arterial blood gas analysis before the initiation of ventilatory support and after sessions of ventilatory support | up to 24 hours | 
| Change in PaO2 | Blood gas parameters will be measured from standard laboratory arterial blood gas analysis before the initiation of ventilatory support and after sessions of ventilatory support | up to 24 hours | 
| Respiratory rate | Clinical parameters will be monitored by physician at baseline and throughout ventilatory support sessions, according to the international guidelines for NIV monitoring | up to 24 hours | 
| Signs of increased work of breathing (use of accessory respiratory muscles, paradoxical motion of the abdomen) | Use of accessory respiratory muscles and paradoxical motion of the abdomen will be assessed by physician at baseline and after sessions of ventilatory support, on a 5 point likert scale (from 1 : absence to 5 : maximal use or accessory respiratory muscle and paradoxical motion of the abdomen) | up to 24 hours | 
| Perceived dyspnea | Dyspnea will be assessed by the patient using a Modified Borg scale for dyspnea, at baseline and after sessions of ventilatory support. Difficulty of breathing will be quantified on a scale from 0 : no difficulty at all to 10 : breathing difficulty is maximal. | up to 24 hours | 
| Treatment failure (composite of change of treatment arm / need for invasive mechanical ventilation/ mortality) | Failure will be defined by a composite of clinical or gasometric worsening or patient intolerance inducing a change of treatment arm/ need for orotracheal intubation and/or mortality (all causes). | Up to Day 28 | 
| Weaning from ventilatory support | Delay from initiation of ventilatory support to weaning | Up to Day 28 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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respiratory insufficiency, Hypercapnic Acute Respiratory Failure, chronic obstructive pulmonary disease exacerbation, nasal high flow, non invasive ventilation, emergency department, critical are