Pilot Study of High-flow Humidified Nasal Oxygen During Breaks From Noninvasive Ventilation

Study Overview
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Brief Summary
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The purpose of this study is to assess whether Optiflow, a high-flow humidified oxygen delivery system, is superior to standard oxygen therapy during breaks off noninvasive ventilation in patients affected by acute respiratory failure and in respiratory distress. The investigators anticipate that the Optiflow will provide oxygen more effectively, be more comfortable and permit longer breaks off NIV, shortening the total duration of NIV.

Detailed Description
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Background: Noninvasive ventilation (NIV) provides respiratory support to many patients affected by acute respiratory failure. This treatment, compared to invasive mechanical ventilation, allows patients to take intermittent breaks during which oxygen therapy is provided through a nasal cannula or mask. During these breaks, the lack of ventilator support may predispose to respiratory distress, retention of CO2 and oxygen desaturation. Optiflow is a nasal humidified (37◦C, 44mg/L H2O) high-flow (up to 60 L/min) therapy which can provide greater support than standard oxygen therapy during the breaks from NIV. Aim of the study is to evaluate Optiflow as an alternative to standard oxygen therapy during breaks from NIV in patients with acute respiratory failure. The investigators hypothesize tha Optiflow will reduce the total length of stay on NIV, and increase the comfort and length of the breaks. Also, the investigators anticipate that it will reduce respiratory rate, accessory muscle use and dyspnea score compared to standard oxygen therapy. Experimental design Prospective open-label, parallel, randomized (1:1) controlled study, with a target enrollment of 70. Study procedures Enrolled patients receiving NIV will be randomized into two arms; a treatment group which will receive Optiflow during breaks and a control arm which will receive standard oxygen therapy during breaks. In both cases, FiO2 will be titrated to maintain oxygen saturation above 90%. The necessity of breaks will be determined together with the patients (talk, eat, medication, communicate with family, inability to tolerate the interface), and the need to resume NIV will be based on clinical data, such as dyspnea, respiratory rate, heart rate, blood pressure, oxygen saturation, transcutaneous carbon dioxide (CO2) and patients' desire. Recorded data: The investigators will record demographic baseline data; Glasgow Coma Scale, respiratory and heart rate, blood pressure, dyspnea score, accessory muscle use, and comfort score at randomization, at the end of each NIV session and NIV break; the length of each NIV session and break; the medications administered and all the arterial blood gases (ABG) on a daily basis. Moreover the investigators will record the NIV parameters and inspired oxygen fraction (FiO2) at each session and break. Risks: The investigators don't anticipate any significant risks related to the study procedures and equipment. Some patients may not tolerate the Optiflow and some patients may fail NIV and require intubation.

Official Title
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Pilot Study of Optiflow as a NIV Rest Therapy

Conditions
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Acute Respiratory Failure, Treatment With Noninvasive Positive Pressure Ventilation

Intervention / Treatment
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* Device: High-flow humidified nasal oxygen delivery system
* Device: Standard oxygen therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients of 18 or more years of age treated with Bipap or CPAP as per hospital protocol, with an underlying clinical diagnosis of acute respiratory failure. Patients that, prior to administration of NIV, had persistent respiratory acidosis with a pH <7.35 and arterial CO2 > 45 mmHg despite controlled oxygen therapy and standard medical management i.e. bronchodilators, corticosteroids and antibiotics, or Patients with hypoxemic respiratory failure with a PaO2/FiO2 ratio < 300 and respiratory rate ≥ 24. Anticipated duration on NIV of at least 24 hrs Exclusion criteria: Usual contraindications to NIV Respiratory arrest Unable to fit mask Medically unstable or multiple organ failure or unstable coronary disease Agitated or uncooperative Unable to protect airways Swallowing difficulties Excessive secretions not managed by clearance techniques Recent upper airway or gastro-intestinal surgery Facial deformity or previous head and neck surgery Undrained pneumothorax NIV failure within first 2 hours (either intolerance or requirement for intubation) Managed for greater than 48 hours on NIV prior to randomization Disorientation, confusion, unable to rate comfort or dyspnea Expected to require NIV for fewer than 24 hrs from the time of enrollment Patient previously in study Patients on CPAP nighttime only due to OSA Withdrawal/Termination criteria: Patients will be withdrawn from the study when NIV fails and/or the patient is intubated.

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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Optiflow<br>High-flow humidified nasal oxygen delivery system | Device: High-flow humidified nasal oxygen delivery system<br>* During breaks from NIV oxygen will be provided through the Optiflow with FiO2 and flow-rate titrated to maintain the oxygen saturation (SpO2) above 90%.<br>* Other names: Optiflow;|
| Active Comparator: Oxygen therapy<br>Standard oxygen therapy | Device: Standard oxygen therapy<br>* During breaks from NIV oxygen will be provided by standard nasal cannula or mask to maintain the SpO2 above 90%.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of stay on NIV | The investigator will measure the total time on NIV in day(s), hours and minutes | Day 4-10 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| NIV-related complications |  | day 4-10 | 
| Length of breaks from NIV |  | Day 4-10 | 
| Assessment of respiratory distress | Evaluation of respiratory distress through respiratory rate, dyspnea score using Borg scale and accessory muscle use | day 2-4 | 
| Patients' comfort | Using a visual analogue scale (VAS) | Day 2-4 | 
| Gas exchange during breaks | Using SpO2 and transcutaneous CO2 | day 2-4 | 
| NIV failure |  | day 2-10 | 
| Need for intubation |  | Days 2-10 | 
| Ease of eating |  | Day 2-4 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Optiflow, Humidified high-flow oxygen therapy, Noninvasive ventilation, Acute respiratory failure, Standard oxygen therapy