Evidence-based indications for noninvasive positive-pressure ventilation (NPPV) according to the severity and time of acute respiratory failure (ARF) [18]. Evidence-based indications for noninvasive positive-pressure ventilation (NPPV) according to the severity and time of acute respiratory failure (ARF) [18]. COPD: chronic obstructive pulmonary disease; ACPE: acute cardiogenic pulmonary oedema; CAP: community-acquired pneumonia; ARDS: acute respiratory distress syndrome. Raffaele Scala, and Lara Pisani Eur Respir Rev 2018;27:180029 ©2018 by European Respiratory Society