AbstractObjectives(1) To examine whether infants with severe bronchiolitis, fulfilling criteria for further respiratory support, could be managed outside a Pediatric Intensive Care Unit (PICU) with non‐invasive ventilation (NIV) alone. (2) To study the characteristics, clinical course and outcome of NIV responders and non responders to assess safety and efficacy and inform guideline construction.HypothesisInfants with severe bronchiolitis can be safely managed with NIV outside a PICU.Study DesignRetrospective case review.Patient SelectionCohort of infants with objective evidence of severe bronchiolitis requiring respiratory support nursed in a Pediatric High Dependency Unit (PHDU) and/or Intensive Care Unit (ICU) between 2001 and 2007.MethodologyAnalysis of patient characteristics and respiratory parameters at admission and initiation of ventilation, changes after 2 and 4 hr of NIV or invasive ventilation, complications, short and long‐term outcomes were analyzed.ResultsOne thousand and thirty‐five infants with bronchiolitis were admitted with 67 ventilation episodes identified from 65 patients. Fifty‐five episodes, including 34 with apnea, were treated exclusively with NIV. Six infants failed to respond and were invasively ventilated. Six patients were invasively ventilated at presentation. Non‐responders had a significantly higher rate of bacterial infection. Significant improvements in respiratory parameters in responders occurred by 2 hr and sustained at 4 hr. Duration of hospital stay, ventilation requirement and oxygen requirement were significantly shorter in responders. Short and longer‐term follow up data did not identify any adverse effects related to NIV.ConclusionsNIV was effective in 80% of infants receiving respiratory support for severe bronchiolitis. Pediatr Pulmonol. 2012. 47:909–916. © 2012 Wiley Periodicals, Inc.