A Randomised Controlled Trial of High-Flow Nasal Oxygen Versus Standard Oxygen Therapy in Critically Ill Immunocompromised Patients

Study Overview
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Brief Summary
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Acute respiratory failure (ARF) is the leading reason for ICU admission in immunocompromised patients. Usual oxygen therapy involves administering low-to-medium oxygen flows through a nasal cannula or mask [with or without a bag and with or without the Venturi system] to achieve SpO2≥95%. Oxygen therapy may be combined with non-invasive ventilation [NIV] providing both end-expiratory positive pressure and pressure support. However, in a recent trial by our group, non-invasive ventialtion [NIV] was not superior over oxygen without NIV. High-flow nasal oxygen [HFNO] therapy is a focus of growing attention as an alternative to standard oxygen therapy. By providing warmed and humidified gas, HFNO allows the delivery of higher flow rates [of up to 60 L/min] via nasal cannula devices, with Fraction of inspired oxygen (FiO2) values of nearly 100%. Physiological benefits of HFNO consist of higher and constant FiO2 values, decreased work of breathing, nasopharyngeal washout leading to improved breathing-effort efficiency, and higher positive airway pressures associated with better lung recruitment. Clinical consequences of these physiological benefits include alleviation of dyspnoea and discomfort, decreases in tachypnoea and signs of respiratory distress, a diminished need for intubation in patients with severe hypoxemia, and decreased mortality in unselected patients with acute hypoxemic respiratory failure However, although preliminary data establish the feasibility and safety of this technique, HFNO has never been properly evaluated in immunocompromised patients. Thus, this project aims at demonstrating that HFNO is superior to low/medium-flow (standard) oxygen, minimising day-28 mortality

Detailed Description
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After discussion at the investigator meeting and based on comments from the Data and Safety Monitoring Board on May 12, 2016, the DSMB has highlighted the need of the interim analysis (already planned) as benefits from high flow oxygen may be observed after 400 inclusions. Update on June 16, 2017: The number of patients enrolled is 488 and the inclusion rate is increasing steadily. The interim analysis has been performed as scheduled and the DSMB decided that nothing should be changed.

Official Title
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A Randomised Controlled Trial of High-Flow Nasal Oxygen Versus Standard Oxygen Therapy in Critically Ill Immunocompromised Patients

Conditions
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Acute Respiratory Failure

Intervention / Treatment
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* Procedure: standard oxygen
* Procedure: HFNO


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Known immunosuppression defined as one or more of the following: (a) immunosuppressive drug or long-term [>3 months] or high-dose [>0.5 mg/kg/day] steroids; (b) solid organ transplantation; (c) solid tumour; (d) haematological malignancy. ICU admission for any reason Need for oxygen therapy ≥6 Liters/min defined as one or more of the following: (a) respiratory distress with a respiratory rate >30/min; (b) cyanosis; (c) laboured breathing; (d) SpO2<90%; and (e) expected respiratory deterioration during a procedure Written informed consent from the patient or proxy (if present) before inclusion or once possible when patient has been included in a context of emergency. Exclusion Criteria: Patient admitted to the ICU for end-of-life care. Do-not-intubate (DNI) patients can be included. Refusal of study participation or to pursue the study by the patient Hypercapnia with a formal indication for NIV [PaCO2 ≥ 50 mmHg, formal indication for NIV] Isolated cardiogenic pulmonary oedema [formal indication for NIV]. Patients with pulmonary oedema associated with another ARF etiology can be included. Pregnancy or breastfeeding Anatomical factors precluding the use of a nasal cannula Absence of coverage by the French statutory healthcare insurance system Post surgical setting from D1 to D6 After discussion at the investigator meeting and based on comments from the Data and Safety Monitoring Board on May 12, 2016, as all included patients need to have an acute hypoxemic respiratory failure and at least 6l of oxygen per minute, patients admitted to the ICU to secure any procedure (bronchoscopy etc..) or those not admitted for acute respiratory failure and who undergo intubation, will NOT be included in this trial. Only patients meeting criteria of acute respiratory failure will be included in this trial.

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: standard oxygen group<br>Oxygen therapy will be delivered using any device or combination of devices that are part of usual care: nasal oxygen, and mask with or without a reservoir bag and with or without the Venturi system | Procedure: standard oxygen<br>* Devices used to treat spontaneously ventilating patients in the ICU who require supplemental oxygen. They deliver either low-flow oxygen [including nasal cannula, Ventimask® without Venturi effect, and non-rebreather mask] or medium-flow oxygen [Venturi masks and medium-flow facemasks]<br>|
| Experimental: High-flow nasal oxygen (HFNO) group<br>Device that delivers humidified and warmed high-flow oxygen at flows greater than 15 L/min. HFNO will be initiated at a flow rate of 50 L/min and 100% FiO2. If the target SpO2 is not reached, the flow rate will be increased to 60 L/min. Then, FiO2 will be tapered to target an SpO2≥95. The minimal flow rate will be 45 L/min | Procedure: HFNO<br>* The intervention is the use of a device that allows to deliver high flow humidified and warmed oxygen. The device used is the Optiflow™ (Fisher&Paykel, Courtaboeuf, France).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| All-cause day-28 mortality |  | 28 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intubation or reintubation rate | proportion of patients requiring invasive mechanical ventilation | days 3 and 28 | 
| patient comfort | Visual Analogue Scale (VAS) score | 28 days | 
| Intensity of dyspnoea | Visual Analogue Scale (VAS) score | days 1-3 | 
| Perceived Exertion | Borg scale | days 1-3 | 
| Respiratory rate |  | days 1-3 | 
| Oxygenation | based on continuous saturation of peripheral oxygen (SpO2) monitoring, lowest SpO2 from D1 to D3 and PaO2/FiO2 on D1, D2, and D3 | days 1-3 | 
| ICU length of stay |  | 28 days | 
| Incidence of ICU-acquired infections |  | 28 days | 
| Time to clear pulmonary infiltrates | Murray score | 28 days | 
| Oxygen-free and ventilation-free survivals |  | day 28 | 
| Re-intubation rate |  | day 28 | 
| Lowest median SpO2 during intubation | for patients who were intubated during the study period | days 1-3 | 
| Repartition of acute mild/moderate/severe respiratory distress syndrome (ARDS) stages after intubation or reintubation as defined by the Berlin definition |  | day 28 | 
| Hypoxemic cardiac arrests | After discussion at the investigator meeting and based on comments from the Data and Safety Monitoring Board on May 12, 2016, all hypoxemic cardiac arrests will be considered as suspected unexpected serious adverse reaction | day 28 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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immunocompromized patients, critically ill patients