Severe acute bronchiolitis (SAB) can be life-threatening for infants and may be responsible for the congestion of intensive care units (ICU) during epidemics. We aimed to study the clinical and paraclinical characteristics of patients with SAB requiring a transfer to the ICU in order to examine their outcomes and to identify the predictors of a stay of ≥7 days and/or death.

This was a cross-sectional retrospective study including infants aged ≤12 months transferred to the ICU for their first episode of SAB between 1 January 2010 and 31 December 2019.

We collected data on 380 patients with a median age of 1.75 months. They had a history of prematurity (20.53 %), low birth weight (18.68 %), parental atopy (12.89 %), and comorbidity (7.37 %, mainly congenital heart disease [5 %]). The leading cause of transfer was hypoxemia and increased oxygen requirements (49.73 %). The patients required mechanical ventilation (MV) in 63.42 % of the cases and noninvasive ventilation (NIV) in 67.63 %. NIV has supplanted MV over the years. Its use has increased from 40.4 % in 2010 to 96 % in 2019 compared with 83.84 % and 42 % for MV. A total of 14 (3.68 %) patients died. The independent predictors of a stay of ≥7 days and/or death were young age ≤2 months (p = 0.002), failure to thrive (p = 0.006), apnea (p = 0.045), dehydration (p = 0.018), the presence of biological inflammatory reaction (p = 0.002), isolation of respiratory syncytial virus (p < 0.001), and bacterial coinfection (p = 0.013).NIV was a protective factor (p < 0.001). A severity score ranging from 0 to 17 was established with an optimal cut-off value of 5 points.

Specific caution is needed in patients with these severity predictors. The generalization ofNIV in general pediatrics departments would improve SAB management and reduce transfers to the ICU.