Although a considerable amount of experimental data exists, preliminary clinical studies of pressure and volume limited ventilation have not established its role and benefit in patients with acute lung injury. Indeed, there are no controlled studies that prove any form of mechanical ventilation is superior to another in ARDS. Prone positioning should be considered early in the course of ARDS, not only for treatment of hypoxia but also for its potential lung-protective effects. Tracheal gas insufflation shows promise in alleviating troublesome hypercarbia associated with pressure and volume limited ventilation. For appropriate patients, the obvious and more insidious complications associated with tracheal intubation may be avoided with the use of NIV. NIV has clearly found a important role in the management of ARF secondary to COPD. www.jiuxin-med.com