Ultrasound Evaluations of Diaphragm and Intercostal Muscle to Predict the Failure of High-Flow Nasal Cannula Therapy

Exclusion Criteria

• •received mechanical ventilation, including invasive or noninvasive ventilation within one month prior to enrollment
• •history of neuromuscular disorders (e.g., myasthenia gravis, Guillain-Barre syndrome);
• •immediate endotracheal intubation is required (life-threatening hypoxemia)
• •extensive damage to the thoracic skin (e.g., burns) unable to undergo ultrasonography
• •pregnancy
• •attending physician deemed it inappropriate to participate in the trial.