We have read with considerable interest the recent investigation by Tabbì and colleagues elucidating inspiratory muscle activity through ultrasonographic assessment in patients with chronic obstructive pulmonary disease (COPD) presenting with acute hypercapnic respiratory failure[1]. This scholarly work provides a seminal contribution to the field by employing a comprehensive, multimuscle approach to evaluate diaphragmatic and extradiaphragmatic muscle function during high flow nasal cannula therapy.
