High-Flow Nasal Cannula Therapy: Mechanisms, Clinical Applications, And Outcomes In Adult Acute Hypoxemic Respiratory Failure

Abstract

High-flow nasal cannula (HFNC) therapy has emerged as a pivotal intervention in respiratory care, bridging the gap between conventional oxygen therapy and invasive mechanical ventilation. This paper examines the physiological mechanisms underlying HFNC effectiveness, reviews current evidence for its clinical applications in acute hypoxemic respiratory failure, and analyzes patient outcomes compared to traditional oxygen delivery methods. A comprehensive literature review reveals that HFNC provides superior oxygenation through multiple mechanisms including positive end-expiratory pressure (PEEP) effect, dead space washout, and consistent FiO₂ delivery. Clinical evidence demonstrates reduced intubation rates and improved patient comfort in selected populations. However, careful patient selection and monitoring remain essential to prevent delayed intubation in deteriorating patients. This paper provides evidence-based recommendations for respiratory therapists implementing HFNC in acute care settings.