Respiratory rate and peak inspiratory pressure, new targets from the LUNG SAFE study analysis or physiopathological artifacts?

Acute respiratory distress syndrome (ARDS) will celebrate in 2017, his golden fiftieth anniversary since his first description by Ashbaugh and colleagues in 1967 (1). This long period of time has permitted many advances in pathophysiological concepts as the emerging role of ventilator-induced lung injury (VILI) (2). Unfortunately, relevant interventions allowing a better outcome are still scarce and include the use of low tidal volume (TV) ventilation (3) for all ARDS patients and the use of systematic prone positioning (4) and early short term neuromuscular blocking agents (5) for the most severe forms of ARDS. To better classify, to design high quality clinical trials and in order to stratify treatments and outcomes, a new definition so called the Berlin definition was published in 2012 (6). The LUNG SAFE study (7) is a global word wide epidemiological study of the burden of ARDS across the five continents. Beside the still crude 40% in hospital mortality of the disease, the LUNG SAFE study has under lightened the misrecognition and under recognition of the syndrome leading to potential inadequate treatments. Therefore, Dr. Laffey and colleagues performed a secondary analysis (8) of potentially modifiable factors contributing to outcome from the LUNG SAFE study whose aims were, first to identify management’s factors associated such as ventilator-related parameters and second to investigate the role of non modifiable factors such as demographic characteristics, severity of illness and the variables associated with decisions of withholding or withdrawing treatments.