Prone Position Effects on Work of Breathing and Intrinsic PEEP in Children With Severe Acute Viral Bronchiolitis

Study Overview
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Brief Summary
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Acute viral bronchiolitis is the first cause of respiratory distress in infant. Airway inflammation increases the respiratory system resistances and dynamic hyperinflation. This leads to an increase in the work of breathing. In Chronic obstructive pulmonary disease patients as in neonates, prone position (PP) improves lung function and decreases the end expiratory lung volume. The investigators hypothesized that in infants with severe bronchiolitis, prone position reduces the intrinsic Positive End Expiratory Pressure (PEEPi) and the work of breathing (WOB). The investigator designed a prospective randomized crossover study with 16 infants younger than six months who need ventilatory support by nasal continuous positive airway pressure (nCPAP) for severe acute viral bronchiolitis. Work of breathing (product time pressure) and PEEPi will be estimated using an esophageal pressure probe in prone and supine position.

Official Title
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Prone Position Effects on Work of Breathing and Intrinsic PEEP in Children With Severe Acute Viral Bronchiolitis

Conditions
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Severe Bronchiolitis

Intervention / Treatment
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* Procedure: Supine then Prone position
* Procedure: Prone then supine position


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Infant < 6 months Admitted in the pediatric intensive care unit of the Femme-Mère-Enfant hospital, Hospices Civils de Lyon, France With severe acute viral bronchiolitis requiring ventilatory support (mWCAS > 4 and/or and or FiO2> 40% and/or hypercapnic acidosis (pH<7.30 and/or pCO2>8 kPa)) Signed informed consent by the two parents or the owner of parental authority Exclusion Criteria: Chronic respiratory, neuromuscular, ENT or cardiac disease Contraindication for placement of esophageal probe (esophageal surgery, varices, …) Children requiring invasive ventilation (more than 3 significant apneas in 1 hour, decreased consciousness, …) Children not affiliated to a social security scheme

Ages Eligible for Study
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Maximum Age: 6 Months

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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PRONE-Supine<br>We test the hypothesis that in infants with severe bronchiolitis, prone position reduces the work of breathing (WOB) and the intrinsic Positive End Expiratory Pressure (PEEP). | Procedure: Prone then supine position<br>* One hour in prone position with CPAP (+7 cmH2O) then 15 min in supine position in spontaneous ventilation (wash out ) and one hour in supine position with CPAP (+7 cmH2O)<br>|
| Experimental: SUPINE - Prone<br>We test the hypothesis that in infants with severe bronchiolitis, prone position reduces the work of breathing (WOB) and the intrinsic Positive End Expiratory Pressure (PEEP). | Procedure: Supine then Prone position<br>* One hour in supine position with CPAP (+7 cmH2O) then 15 min in supine position in spontaneous ventilation (wash-out) and one hour in prone position with CPAP (+7 cmH2O)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Work of breathing | The primary outcome is the work of breathing (WOB) estimated by the mean on 100 breaths of the esophageal and trans-diaphragmatic Pressure-Time Product (PTP) at the end of the first hour. | 60 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intrinsic PEEP | Mean on 10 breaths of the intrinsic positive end expiratory pressure in spontaneous ventilation | 60 min | 
| Inspiratory:Expiratory Time Ratio | Mean on 100 breaths of the Inspiratory:Expiratory Time Ratio | 60 min | 
| Heart rate | Evolution of the clinical and oxygenation parameter within the first hour in each position. | 60 min | 
| Respiratory rate | Evolution of the clinical and oxygenation parameters within the first hour in each position. | 60 min | 
| SPO2 | Evolution of the clinical and oxygenation parameters within the first hour in each position. | 60 min | 
| Transcutaneous CO2 | Evolution of the clinical and oxygenation parameters within the first hour in each position. | 60 min | 
| EDIN score (neonatal pain and discomfort scale) |  | 60 min | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Children., prone position, acute viral bronchiolitis, syncytial virus, work of breathing, intrinsic PEEP