Evaluating the introduction of Humidified High-Flow nasal cannula therapy into an Australian Aeromedical Service within a paediatric population: A retrospective cohort study.

Title: Evaluating the introduction of Humidified High-Flow nasal cannula therapy into an Australian Aeromedical Service within a paediatric population: A retrospective cohort study. <bold>Aim:</bold> To compare the outcomes of paediatric patients who were initiated on Humidified High Flow (HHF) oxygen in a peripheral centre prior to air transfer to a tertiary paediatric centre, based on whether HHF was continued during the flight. <bold>Methods:</bold> This was a retrospective cohort study assessing outcomes of those rural Western Australian patients initiated on HHF at a retrieving hospital and subsequently did or did not receive HHF in flight to the destination hospital between the four-year period. <bold>Results:</bold> A total of 61 cases were collected, 29 did not receive HHF in flight, 32 continued HHF in flight to the destination hospital. All recorded cases were flight transfers and ranged between 0.65 hours and 4.9 hours. The median age of participants is 8 months (IQR 4,18). The main pathology included bronchiolitis (55%) and pneumonia (33%). Those patients who had a higher respiratory rate (p = 0.021) or had severe work of breathing, the more likely they were to receive HHF in flight (p = 0.012). If a participant had HHF in flight, they were more likely to continue it in the destination hospital (p = <0.001). Between our two groups, there was no observed statistically significant difference of hospital length of stay (p = 0.8). <bold>Conclusion:</bold> Our study adds to a growing body of literature that the use of HHF during aeromedical transfer is safe and did not lead to increased hospital length of stay in our study population.