Chest and Abdominal Wall Strapping in Infant With Bronchiolitis (WRAPITIS)

Effect of Chest and Abdominal Wall Strapping on Ventilation and Work of Breathing in Infants With Severe Bronchiolitis: a Physiological Study

Bronchiolitis is the most common cause of admission to the Paediatric Intensive Care Unit (PICU) for respiratory distress. The care of an infant with severe bronchiolitis is mainly based on symptomatic treatment (nutritional and respiratory support). The lower part of an infant's chest is larger than that of an older child, which can flatten the diaphragm, especially in obstructive disease with air trapping. Strapping the lower part (at the junction of the chest and abdomen) may provide a better condition for diaphragmatic contraction. Based on respiratory mechanics in infants and physiological studies in adults, investigators hypothesise that chest wall strapping may improve the ventilation and the diaphragmatic contraction. Infant < 6 month with severe bronchiolitis admitted to the PICU will be recorded in 4 conditions with or without chest wall strapping and with a Continuous Positive Airway Pressure (CPAP) at 7 cmH2O or without CPAP. Physiological parameters (including work of breathing, respiratory parameters, distribution of ventilation) will be recorded and analysed.

Infant will be recorded successively in 6 conditions (10 min each) : Without chest wall strapping at PEEP (Positive End Expiratory Pressure) 0 and PEEP 7 With chest wall strapping at PEEP 0 and PEEP 7 again without chest wall strapping at PEEP 0 and PEEP 7.

Infant will be recorded successively in 6 conditions (10 min each) : Without chest wall strapping at PEEP 0 and PEEP 7 With chest wall strapping at PEEP 0 and PEEP 7 again without chest wall strapping at PEEP 0 and PEEP 7.

An elastic band (6 cm wide) is placed around the lower part of the chest wall (at the junction of the chest and abdomen) to tighten the chest wall for 10 min at PEEP 7 cmH2O and 10 min without PEEP

Mean on 100 breaths of the amplitude (maximum value -minimum value) of the esophageal pressure (cmH2O) and gastric pressure (cmH2O)

Mean over 1 minute of the center of the ventilation (%). Center of ventilation represents the average of the dorsal-ventral distribution of tidal variation using Electrical Impedance Tomography (values >50% indicating that the center of ventilation is located in the ventral part of the chest)

Value of the modified wood asthma score at the end of the recording period in each condition. Minimal value 0 and maximal value 10. A score ≥ 3 mean a moderate-to-severe respiratory distress.

Value of the EDIN score at the end of the recording period in each condition. Minimal value 0 and maximal value 15. EDIN scores > 6 are considered expression of pain

Inclusion Criteria: Infant < 6 months Admitted to the PICU for less than 48 hours With a diagnosis of bronchiolitis With a respiratory distress sign (mWCAS ≥ 3) and non-invasive ventilatory support With a naso or oro gastric tube for feeding With written informed consent from parents or legal guardians Exclusion Criteria: Infants with severe bronchopulmonary disease, severe laryngomalacia, neuromuscular disease, bone disease, cyanotic heart disease Contraindication to the use of a gastric tube recent abdominal or thoracic surgery investigator able to perform physiological recording not available Patient who is not affiliated (or does not benefit from) to a national social security system