Abstract Rationale Studies have explored high-flow nasal cannula (HFNC) for end-of-life (EOL) symptom management, but its distinct use in DNI patients whose goal is life prolongation is poorly understood. Differentiating HFNC as a respiratory treatment mode versus an EOL care mode is critical to optimizing care in patients wishing to avoid intubation. Methods In this retrospective cohort study utilizing an electronic health record registry of adults treated with HFNC at a 5-hospital system between July 2017- February 2025, we identified hospitalizations for patients who were DNI prior to HFNC initiation or transitioned to DNI after HFNC initiation. We describe the prevalence of DNI status and its overlap with EOL care. Results In 16,612 hospitalizations where HFNC was used, 3,327 (20.0%) involved HFNC use among DNI patients (Table 1). Of the 1,908 (11%) patients initiated on HFNC while DNI but without a “comfort care only” code status, 30% died receiving comfort care in the hospital, 14% died in the hospital without a documented transition to comfort care, and 22% were discharged to hospice. The remaining 35% were discharged alive and not to hospice. 1,192 (7.2% of all HFNC) patients had code statuses compatible with intubation at HFNC initiation but transitioned to DNI while receiving HFNC. This group had the highest overall mortality rate: 20% died receiving comfort care in the hospital and 41% died in the hospital without a documented transition to comfort care. An additional 22% were discharged to hospice. Only 12% were discharged alive and not to hospice. Patients who transitioned to DNI spent longest on HFNC (median duration 47 hours vs 14 hours for patients who were either DNI throughout or “OK to Intubate” throughout, p 0.001); on average, code status changed 11 hours after HFNC initiation and HFNC continued for 24 hours afterwards. Only 227 (1.4%) patients were started on HFNC with a “comfort care only” code status. Conclusions 20% of patients in our cohort were DNI at some point during their HFNC episode. DNI patients are at significantly elevated risk of death, but a third are successfully treated for respiratory failure. In only a small minority of cases was HFNC initiated as a component of comfort care. Further work is needed to understand the motivations and management of the particularly high-risk group of patients who transition to DNI on HFNC. This abstract is funded by: NIH
Bouhassira et al. (Fri,) studied this question.