La ventilation non invasive dans les bronchiolites graves de l'enfant

Three clinical presenting forms can be distinguish in severe bronchiolitis: apnea, hypercapnic respiratory failure and hypoxemic pneumonia. Recent clinical and physiological studies have confirmed the efficacy of noninvasive ventilation (NIV) in this disease: NIV decreases work of breathing, decreases intubation and invasive ventilation rates, and reduces acquired pulmonary bacterial infections. Criteria of NIV initiation and ventilator setting have never been studied in infants. The overall severity, the lack of decrease of respiratory rate in the first two hours following NIV starting and hypoxemic pneumonia were associated with NIV failure. The choice of ventilator mode and interface depends on clinical presenting forms, age and on critical care team's experience. We recommend starting with a continuous positive airway pressure (CPAP) level of 4 or 5 cmH2O, with a rapid increase of level according to the clinical and biological responses. In pressure support ventilation a minimal level of 6 cmH2O is recommended. In infants weighing less than 5 kg nasal prongs are well tolerated and efficient. For bigger infants, nasal mask, naso-buccal mask and helmet can be good alternatives. NIV should be initiated by a well-trained team in a pediatric intensive care unit. A closed monitoring is required and the response to NIV should be assessed within the two or four first hours in order to avoid a delayed intubation, especially in acute hypoxemic pneumonia forms. NIV has profoundly changed the ventilatory support strategy of acute respiratory failure due to bronchiolitis even though many questions remain to be elucidated. Pediatric clinical trials should be encouraged to increase the level of evidence.