“Open the lung and keep it open”: a homogeneously ventilated lung is a ‘healthy lung’

The acute respiratory distress syndrome (ARDS) has been a major cause of morbidity and mortality in the intensive care unit (ICU) for over four decades. What was thought to be a universally fatal form of double pneumonia was first identified in 1967 as a unique clinical entity and is now what we call ARDS. Ashbaugh et al. first identified ARDS as a unique disease triggered by a collection of pathologic abnormalities from initiating injuries such as sepsis, pneumonia, trauma or burns (1). In addition, this group demonstrated that ARDS mortality could be significantly reduced if positive end expiratory pressure (PEEP) was added to the ventilator strategy (1). Mortality secondary to ARDS was almost 70% from 1967–1979 and has been reduced progressively over the decades [60%: 1980–1989; 50%: 1990–1997] to the current mortality of ~40% [1998-2013] (2). Although we have significantly reduced ARDS mortality from when it was first identified, mortality has not been reduced any further over last 15 years (3).