Large Observational Study to UNderstand the Global Impact of Severe Acute Respiratory FailurE

We wish to prospectively assess the burden of, management and therapeutic approaches to, and outcomes from acute hypoxaemic respiratory failure requiring ventilatory support, during the winter months in both the northern and southern hemispheres. We wish to specifically examine the contribution of ARDS as defined by the Berlin Definition to the burden of hypoxaemic respiratory failure. Why? The purpose of this study is to provide new and current data on the disease burden of acute hypoxemic respiratory failure and ARDS. It will answer the following questions: * What is the frequency and disease burden of acute hypoxaemic respiratory failure in winter? * What are the aetiologies of acute hypoxaemic respiratory failure requiring ventilatory support? * What is the incidence of ARDS based on the Berlin definition within this patient cohort? * What is the mortality from ARDS within this cohort, and how does this vary based on ARDS severity? * What is the natural history of ARDS? * What are the key patterns of therapeutic resource utilization, particularly approaches to sustain gas exchange, in these patients? When? The study is performed over a 4 week period between February 1st and March 31st 2014 in the Northern Hemisphere and June 1st to August 31st in the Southern Hemisphere. What data is required? A basic dataset is collected on all patients admitted with acute acute hypoxaemic respiratory failure requiring ventilatory support, with a more detailed dataset collected on patients diagnosed with ARDS.