High-Intensity vs Low-Intensity NPPV and Need for Endotracheal Intubation

To the Editor I have several questions about the recent randomized clinical trial that reported that patients with an acute exacerbation of chronic obstructive pulmonary disease and persistent hypercapnia were less likely to meet criteria for endotracheal intubation when randomized to high-intensity vs low-intensity noninvasive positive pressure ventilation (NPPV). I would be grateful if the authors could provide a description of the type of interface used for the NPPV (eg, nasal mask, face mask, face shield, helmet).