Table 2. The American European Consensus Conference (AECC) definition of acute lung injury and acute respiratory distress syndrome (ARDS) [1994].

Diagnostic criteria for acute lung injury (ALI)

Time: acute onset

Oxygenation: PaO2/FiO2 ≤300 mmHg (regardless of PEEP level used)

CXR: bilateral infiltrates

Pulmonary capillary pressure ≤18 mmHg/No evidence of left atrial hypertension

Diagnostic criteria for ARDS

Same as ALI, except for oxygenation: PaO2/FiO2 ≤200 mmHg

PEEP, positive end expiratory pressure; CXR, chest X-ray.