1045Objectives: To compare outcomes of children receiving noninvasive ventilation with those receiving invasive ventilation as first-line mode of mechanical ventilation following unplanned intensive care admission. Design: Propensity score-matched cohort study analyzing data prospectively collected by the Pediatric Intensive Care Audit Network over 8 years (2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014). Setting: Thirty-one PICUs in the United Kingdom and Ireland; twenty-one of whom submitted Pediatric Critical Care Minimum Dataset data for the entire study period. Patients: Children consecutively admitted to study PICUs. Planned admissions following surgery, unplanned admissions from other hospitals, those on chronic ventilation, and those who did not receive mechanical ventilation on the day of PICU admission were excluded. Interventions: Use of noninvasive ventilation, rather than invasive ventilation, as the first-line mode of mechanical ventilation. Measurements and Main Results: PICU mortality, length of ventilation, length of PICU stay, and ventilator-free days at day 28. During the study period, there were 151,128 PICU admissions. A total of 15,144 admissions (10%) were eligible for analysis once predefined

Objectives: To: 1) describe patterns of use of high flow nasal cannula therapy (HFNC); 2) examine differences between patients started on HFNC and those started on non-invasive ventilation (NIV); and 3) explore whether patients who failed HFNC therapy were different from those who did not. Design: Retrospective analysis of data collected prospectively by the Paediatric Intensive Care Audit Network (PICANet). Setting: All paediatric intensive care units (PICUs) in the United Kingdom and Republic of Ireland (n=34). Patients: Admissions to study PICUs (2015-16) receiving any form of respiratory support at any time during PICU stay. Interventions: None. Measurements and Main Results: Eligible admissions were classified into nine groups based on the combination of the first-line and second-line respiratory support modes. Uni-and multivariate analyses were performed to test the association between PICU and patient characteristics and two outcomes: a) use of HFNC versus NIV as first-line mode, and b) HFNC failure, requiring escalation to NIV and/or invasive ventilation (IV). We analysed data from 26,423 admissions; HFNC was used in 5,951 (22.5%) at some point during the PICU stay. HFNC was used for first-line support in 2,080 (7.9%) and post-extubation support in 978 admissions (4.5% of patients extubated after first-line IV). HFNC failure occurred in 559/2080 admissions (26.9%) when used for first-line support. Uni-and multivariate analyses showed that PICU characteristics as well as patient age, primary diagnostic group 4 and admission type had a significant influence on the choice of first-line mode (HFNC or NIV). Younger age, unplanned admission and higher admission severity of illness were independent predictors of HFNC failure. Conclusions: The use of HFNC is common in PICUs in the UK and Republic of Ireland. Variation in the choice of first-line respiratory support mode (HFNC or NIV) between PICUs reflects the need for clinical trial evidence to guide future practice.