The main goals of NPPV in patients with parenchymal lung disease, such as pneumonia, acute lung injury (ALI), and acute respiratory distress syndrome (ARDS), are to improve oxygenation, to unload the respiratory muscles, and to relieve dyspnea. The first goal can usually be achieved by using EPAP to recruit and stabilize previously collapsed lung tissue [39] . Unloading of the respiratory muscles during NPPV with IPAP has been reported by L'Her et al. in adult patients with ALI [39] . The authors concluded that adding IPAP to EPAP may be indispensable in patients with ALI treated with NPPV [39] . Indeed, IPAP allows a better respiratory system muscle unloading, alveolar recruitment, oxygenation, and CO 2 washout improvement. Although NPPV seems disappointing in ARF owing to pneumonia in adult patients, with failure rates of up to 66% [40] , several noncontrolled trials have suggested that NPPV could improve symptoms and ventilation without significant adverse events and reduce the need for IMV in children with ARF due to pneumonia [22] [23] [24] [25] [26] [27] . Use of NPPV in this acute setting in children was associated with reduction in ETI rates ranging from 50-100% (Table 1) [23, 24] .