Since 1987, several studies were designed in order to evaluate whether NPPV could also be used in patients with acute respiratory failure; however, if the long-term use of NPPV seems to be characterized by minimal side effects (nasal abrasion;* mask leaks; abdominal distension), NPPV in acute situations is not simple to use. Some patients ventilated via a face mask in acute respiratory failure must be eventually intubated, and several complications of acute NPPV have been clearly described (ie, leaks or displacement of the mask, severe gastric or ophthalmologic problems).
Therefore, this technique can rarely be used for more than 20 hours per day, and only during a few consecutive days. It soon appeared that acute NPPV seemed more useful in restrictive than in obstructive disorders, an observation quite consistent with the data on chronic positive-pressure home mechanical ventilation; however, some authors clearly mentioned that acute NPPV is very timeconsuming for the ICU team. The monitoring of an intubated patient is simple and a classic ICU procedure, contrasting with the difficult supervision of an acutely ill patient equipped with a nasal mask, who is fully conscious but rather uncomfortable. Nonetheless, we were unable to find a precise description in the literature of the time spent by nurses or other healthcare professionals with patients in acute respiratory failure who are receiving NPPY even in a recent publication by a French group using facial masks in acutely decompensated patients with COPD.