Abstract Rationale High-flow nasal cannula (HFNC) is an important treatment for respiratory failure. Contemporary practice patterns and outcomes have not been measured at system-wide scale. The objective of this study was to characterize real-world HFNC use and outcomes in a diverse multi-hospital health system. Methods This was a retrospective observational study using an electronic health record registry of all adult patients in a 5-hospital system between 2017-2025. We identified all episodes in which HFNC was received continuously with breaks no longer than 6 hours. We performed descriptive analysis and regression. Contributors to variability in outcomes across hospitals were assessed using mixed hierarchical models. Results 28,269 HFNC episodes from 17,519 individual patients over 19,313 hospitalizations were identified. Average monthly number of HFNC episodes across the health system increased from 176 episodes/month in early 2017 to 269 episodes/month overall by late 2024 (p 0.001). Most HFNC use was initiated in the ICU (68%), but a significant minority (15%) began outside of a critical care space. 84% of HFNC use was escalation respiratory therapy with the remainder being HFNC used within 24 hours of extubation (Figure 1). Median episode duration was 13.9 4.3-36 hours. 24.5% of episodes were followed by intubation during the same hospitalization, and 29.3% by death or hospice discharge. Illness severity, admitting service, hospital type and initiating unit type were associated with adjusted odds of intubation. 16% of the variation in mortality after HFNC, and 20% of the variation in intubation after HFNC was attributable to hospital-level variation rather than measured patient- and acute-illness factors. Conclusions HFNC is used in multiple hospital settings and contexts. In absolute numbers, the use of HFNC has increased between 2017 and 2025. HFNC outcomes relate not only to patient characteristics but also to the contexts in which HFNC is used. This abstract is funded by: NIH
Bouhassira et al. (2026) studied this question.