Figure 1.

Berlin criteria for the diagnosis of ARDS. These criteria were decided on by a panel of experts from the American Thoracic Society, the Society of Critical Care Medicine, and the European Society of Intensive Care Medicine in 2012 and were a modification from the previously widely used American-European Consensus Conference criteria. The Berlin criteria stipulate that the maximum period between risk factor exposure and development of ARDS be within 7 d, in addition to the requirement for chest imaging and exclusion of hydrostatic pulmonary edema. The Berlin criteria also further classified severity of illness based on oxygen and a minimum level of support with PEEP or CPAP. ARDS indicates acute respiratory distress syndrome; CPAP, continuous positive airway pressure; Fio₂, fraction of inspired oxygen; Pao₂, partial pressure of oxygen; PEEP, positive end-expiratory pressure.