At the time of acute exacerbations of chronic airflow obstruction (BPCO) non-invasive ventilation represents an alternative to endotracheal intubation. In patients with respiratory distress, the use of a face mask is often preferable to a nasal mask alone, by avoiding the escape of oxygen which occurs around the mouth in nasal ventilation. The inspiratory aid is a type of ventilation which permits good synchronisation with the spontaneous activity of the patient; it leads to a reduction of respiratory effort developed by the patient and at the same time improves oxygenation and alveolar ventilation. In a recent randomised multicentre trial in 85 BPCO patients with severe respiratory distress, the level of intubation was reduced from 74 to 26 per cent by ventilation with an inspiratory mask. The consequences were a significant reduction of the complications of acute respiratory failure which were linked to artificial ventilation (p < 0.05) with a reduction of the hospital stay (p < 0.05) and finally a significant reduction in mortality (29 per cent - 9 per cent, p < 0.005). From now on, this technique could be used in many centres as the first treatment in acute exacerbations of BPCO patients to avoid the use of endotracheal intubation.