CPAP Therapy Through a Helmet or a Full Face Mask in Patients With Acute Hypoxemic Respiratory Failure: Cross-over Study

Study Overview
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Brief Summary
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Observational and randomized trials have demonstrated the high effectiveness of non-invasive helmet ventilatory support, demonstrating a reduction in intubation rate mortality compared with high-flow and standard oxygen therapy. Some pilot physiological studies have shown physiological benefits of helmets compared to the oronasal mask for non-invasive ventilation. The purpose of the study is to compare markers of patient self-inflicted lung injury (P-SILI), patient's comfort, work of breathing, gas exchange, and hemodynamics in patients with acute hypoxemic respiratory failure (AHRF) during non-invasive ventilation (NIV) in continuous positive pressure (CPAP) mode during an oronasal mask ventilation or a combination of a helmet with high-flow oxygenation as an air flow generator.

Detailed Description
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In December 2019, an outbreak of a novel coronavirus emerged in Wuhan, China and rapidly spread worldwide. The World Health Organization (WHO) declared the outbreak a pandemic on March 11th, 2020. The clinical disease (COVID-19) results in critical illness in about 5% of patients with predominant acute respiratory failure. Observational and randomized trials have demonstrated the high effectiveness of non-invasive helmet ventilatory support, demonstrating a reduction in intubation rate mortality compared with high-flow and standard oxygen therapy. Some pilot physiological studies have shown physiological benefits of helmets compared to the oronasal mask for non-invasive ventilation. The purpose of the study is to compare markers of patient self-inflicted lung injury (P-SILI) (measuring esophageal pressure, transpulmonary pressure during inspiration and expiration), the patient's work of breathing (assessment of accessory muscles work) patient's comfort by visual-analog scale, gas exchange (by PaO2/FiO2 and Respiration Oxygenation Index (ROX-index), and hemodynamics in patients with acute hypoxemic respiratory failure (AHRF) during non-invasive pulmonary ventilation (NIV) in continuous positive pressure (CPAP) mode during an oronasal mask ventilation or a combination of a helmet with high-flow oxygenation as an air flow generator.

Official Title
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CPAP Therapy Through a Helmet or a Full Face Mask in Patients With Acute Hypoxemic Respiratory Failure: a Comparative, Cross-over, Physiological Study

Conditions
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Pneumonia, Bacterial, Respiratory Failure, COVID-19 Pneumonia

Intervention / Treatment
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* Diagnostic Test: Arterial blood gases
* Diagnostic Test: Respiratory rate (RR)
* Diagnostic Test: Pulseoximeter
* Diagnostic Test: Assessment of accessory respiratory muscles work
* Diagnostic Test: Esophageal pressure measurement
* Diagnostic Test: Discomfort Visual Analog Scale (VAS)
* Diagnostic Test: Noninvasive blood pressure
* Diagnostic Test: Heart rate


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with acute hypoxemic respiratory failure due to community-acquired pneumonia or COVID-19 The ratio of the partial pressure of oxygen in arterial blood to the inspiratory fraction of oxygen (PaO2/FiO2) is less than 250 mm Hg while breathing atmospheric air Respiratory rate more than > 25 per minute. Written informed consent Exclusion Criteria: Patients who achieve the following target parameters with only low-flow oxygen therapy (flow up to 15 l/min): SpO2 > 93%, the patient does not have a subjective feeling of fatigue, there is no visible work of the auxiliary respiratory muscles of the neck, Unstable hemodynamics (systolic blood pressure <90 mm Hg or mean arterial pressure <65 mm Hg) and/or lactic acidosis (lactate >5 mmol/l and/or clinically diagnosed shock) and/or life-threatening arrhythmia, Metabolic acidosis (pH <7.30); Patients who were in the ICU for less than 24 hours for any reason Primary or secondary lung diseases (exacerbation of chronic obstructive pulmonary disease (COPD), bronchial asthma, interstitial lung diseases, metastatic lung disease) Cardiogenic pulmonary edema, Chronic diseases in the stag e of decompensation with the development of extrapulmonary organ dysfunction (liver cirrhosis, progression of cancer, CHF), Glasgow Coma Scale score <14 points, Swallowing disorders Hypercapnia (PaCO2>45 mmHg), The need for urgent tracheal intubation for any reason, Recent head surgery or anatomy that prevents the placement of a helmet or full face mask on the patient, Pregnancy, Inability to cooperate with staff

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: Crossover Assignment
Interventional Model Description: Enrolled patients will receive all types of respiratory support (helmet CPAP 40 minutes followed by full face mask CPAP 40 minutes or full face mask CPAP 40 minutes followed by helmet CPAP 40 minutes) in a randomized crossover design.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Helmet-CPAP then Mask-CPAP<br>CPAP via Helmet 40 minutes, then CPAP via full face mask 40 minutes | Diagnostic Test: Arterial blood gases<br>* Measurement of arterial oxygen and tension and arterial dioxide tension, calculation of arterial partial oxygen tension to inspiratory oxygen fraction (PaO2/FiO2) ratio<br>Diagnostic Test: Respiratory rate (RR)<br>* Measurement of respiratory rate by waveform analysis using a ventilator<br>Diagnostic Test: Pulseoximeter<br>* Peripheral capillary oxygen saturation (SpO2) measurement and the ROX-index calculation (SpO2/FiO2/RR)<br>Diagnostic Test: Assessment of accessory respiratory muscles work<br>* Patrick score calculation. Score: 0. No visible tonic or phasic use of neck muscles. 1. Neck muscles taut but with no respiratory modulation (i.e., tonic activity). 2. Mild respiratory modulation in neck muscle contraction. 3. Moderate phasic activity (no supraclavicular or intercostal indrawing). 4. Vigorous phasic activity with indrawing. 5. Vigorous phasic activity with abdominal paradox.<br>Diagnostic Test: Esophageal pressure measurement<br>* Esophageal pressure measurement on inspiration and expiration with calculation of delta esophageal pressure, transpulmonary pressure and delta transpulmonary pressure<br>Diagnostic Test: Discomfort Visual Analog Scale (VAS)<br>* From 1 to 10 points, where 1 point - maximal discomfort, 10 points - minimal discomfort.<br>Diagnostic Test: Noninvasive blood pressure<br>* Noninvasive blood pressure<br>Diagnostic Test: Heart rate<br>* Heart rate calculation using electrocardiogram monitoring<br>|
| Experimental: Mask-CPAP then Helmet-CPAP<br>CPAP via full face mask 40 minutes, then CPAP via helmet 40 minutes | Diagnostic Test: Arterial blood gases<br>* Measurement of arterial oxygen and tension and arterial dioxide tension, calculation of arterial partial oxygen tension to inspiratory oxygen fraction (PaO2/FiO2) ratio<br>Diagnostic Test: Respiratory rate (RR)<br>* Measurement of respiratory rate by waveform analysis using a ventilator<br>Diagnostic Test: Pulseoximeter<br>* Peripheral capillary oxygen saturation (SpO2) measurement and the ROX-index calculation (SpO2/FiO2/RR)<br>Diagnostic Test: Assessment of accessory respiratory muscles work<br>* Patrick score calculation. Score: 0. No visible tonic or phasic use of neck muscles. 1. Neck muscles taut but with no respiratory modulation (i.e., tonic activity). 2. Mild respiratory modulation in neck muscle contraction. 3. Moderate phasic activity (no supraclavicular or intercostal indrawing). 4. Vigorous phasic activity with indrawing. 5. Vigorous phasic activity with abdominal paradox.<br>Diagnostic Test: Esophageal pressure measurement<br>* Esophageal pressure measurement on inspiration and expiration with calculation of delta esophageal pressure, transpulmonary pressure and delta transpulmonary pressure<br>Diagnostic Test: Discomfort Visual Analog Scale (VAS)<br>* From 1 to 10 points, where 1 point - maximal discomfort, 10 points - minimal discomfort.<br>Diagnostic Test: Noninvasive blood pressure<br>* Noninvasive blood pressure<br>Diagnostic Test: Heart rate<br>* Heart rate calculation using electrocardiogram monitoring<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inspiratory effort | Delta esophageal pressure | 40 minutes | 
| Inspiratory delta transpulmonary pressure (stress) | Inspiratory delta transpulmonary pressure | 40 minutes | 
| Expiratory delta transpulmonary pressure | Expiratory delta transpulmonary pressure | 40 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Oxygenation | PaO2/FiO2 calculation | 40 minutes | 
| Respiratory rate | Measurement of respiratory rate by waveform analysis using a ventilator | 40 minutes | 
| ROX index | Peripheral capillary oxygen saturation (SpO2) measurement and the ROX-index calculation (SpO2/FiO2/RR) | 40 minutes | 
| Patrick's score | Patrick's score measurement, minimum 1point, maximum 5 points, higher score means worse outcome. Score: 0. No visible tonic or phasic use of neck muscles. 1. Neck muscles taut but with no respiratory modulation (i.e., tonic activity). 2. Mild respiratory modulation in neck muscle contraction. 3. Moderate phasic activity (no supraclavicular or intercostal indrawing). 4. Vigorous phasic activity with indrawing. 5. Vigorous phasic activity with abdominal paradox. | 40 minutes | 
| Discomfort visual analog scale (VAS) | Discomfort VAS score calculation, minimum 1point, maximum 10 points, higher score means better outcome | 40 minutes | 
| Noninvasive blood pressure | Noninvasive blood pressure | 40 minutes | 
| Heart rate | Heart rate calculation using electrocardiogram monitoring | 40 minutes |