High-Flow Nasal Cannula Liberation: Who, When, and How?

High-flow nasal cannula (HFNC) is a first-line therapy for patients with acute respiratory failure. Despite increased HFNC utilization over recent years-accelerated in part by the COVID-19 pandemic-high-quality evidence to guide HFNC discontinuation is lacking. Decisions about when and how quickly to reduce flow rate, Fio2, or both simultaneously are frequently left to clinicians' discretion without clear guidance on an optimal approach. Failure to de-escalate HFNC support when clinically appropriate has many potential consequences, such as prolongation of ICU/hospital length of stay, increased health care costs, and reduced availability of limited hospital resources. With the goal of improving care efficiency and resource utilization among hospitalized patients with acute respiratory failure, we propose a standardized approach for HFNC discontinuation focused on "liberation" (similar to spontaneous breathing trials for patients undergoing mechanical ventilation), using a stepwise approach guided by physiology.