Effect of Prone Positioning Combined With High Flow Oxygen Therapy on Oxygenation During Acute Respiratory Failure Due to COVID-19

Study Overview
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Brief Summary
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The main manifestation of COVID-19 is acute hypoxemic respiratory failure (AHRF). In patients with AHRF, the need for invasive mechanical ventilation is associated with high mortality. Prone positioning (PP) is a recommended strategy for patients with moderate to severe acute respiratory distress syndrome (ARDS) undergoing invasive mechanical ventilation. Early PP combined with High Flow Oxygen Therapy may benefit spontaneous breathing patients with AHRF due to COVID-19 as recently reported in Jiangsu. Our hypothesis is that early PP combined with High Flow Oxygen Therapy in patients with AHRF due to COVID-19 improves oxygenation.

Official Title
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Effect of Prone Positioning Combined With High Flow Oxygen Therapy on Oxygenation During Acute Respiratory Failure Due to Sars-covid-2: a Randomized Crossover Trial.

Conditions
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Covid19

Intervention / Treatment
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* Other: Prone position
* Other: Supine position


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged ≥ 18 years, Admitted to ICU within 72 hours, Having confirmed or highly suspected COVID-19 infection (positive RT-PCR and/or computed tomography), Having acute hypoxemic respiratory failure with a [PaO2/FiO2] ratio between 100 mmHg and 300 mmHg, Having given free and informed written consent, Being affiliated with or benefiting from a social security scheme. Exclusion Criteria: Unable to achieve a prone position for mobility reasons, Unable to achieve a prone position due to agitation whatever the cause, With clinical occlusive syndrome in order to limit the risk of inhalation, Having a contraindication to the use of the esophageal catheter, Having signs of respiratory distress or disturbance of consciousness requiring intubation within the next hours, Having hypercapnia indicating the use of non-invasive ventilation (PaO2> 50 mmHg), Having severe hypoxemia defined by PaO2 / FiO2 <100mmHg, Ongoing pregnancy or breastfeeding, Subject to a measure for the protection of justice.

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: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: [PP sequence 1] - Wash-out - [SP sequence 2]<br> | Other: Prone position<br>* prone positioning in spontaneous ventilation<br>Other: Supine position<br>* supine positiong in spontaneous ventilation<br>|
| Other: [SP sequence 1] - Wash-out - [PP sequence 2]<br> | Other: Prone position<br>* prone positioning in spontaneous ventilation<br>Other: Supine position<br>* supine positiong in spontaneous ventilation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| [PaO2 / FiO2] ratio | Oxygenation will be evaluated by the [PaO2 / FiO2] ratio, measured at the beginning (baseline) and at the end of each 2h-sequence by arterial gasometry. The values of this ratio in PP and SP will be compared with each other. | 6 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ΔPeso measured using an esophageal balloon catheter | ΔPeso (cm H2O): defined at each inspiratory cycle as the difference between the esophageal pressure at the end of expiration and at the end of inspiration. | 6 hours | 
| Concentration of CO2 at the end of expiration (EtCO2, mmHg) | Capnometry measurements by breathing on a mouthpiece connected to an online analyzer. The measurements will be made on a 2 min recording (analysis of the curves over a period of 1 min) at the end of each sequence (PP or SP) and compared with each other. | 6 hours | 
| Intensity of dyspnea | assessed by the visual analogue scale for dyspnea (collected at the beginning and at the end of each 2h sequence; the values at the end of each sequence will be compared with each other): 0 = no breathlessness to 10 = worst breathlessness possible | 6 hours | 
| Tolerance of the technique | measured by the visual analogue scale for pain (collected at the beginning and at the end of each 2h-sequence; the values at the end of each sequence will be compared with each other): 0 = no pain to 10 = worst pain possible | 6 hours | 
| Tolerance of the technique | measured by the visual analogue scale for discomfort (collected at the beginning and at the end of each 2h-sequence; the values at the end of each sequence will be compared with each other): 0 = no discomfort to 10 = worst discomfort possible | 6 hours | 
| The occurrence of side effects due to PP | Oxygen desaturation (SaO2 <90%), occurrence of hemodynamic instability (Systolic blood pressure <80 mmHg or heart rate >120 mmHg for >1 minute), accidental withdrawal of venous catheter central or peripheral, accidental withdrawal of arterial catheter, accidental withdrawal of urinary catheter. | 6 hours |