You suspect that the patient has Acute Respiratory Distress Syndrome (ARDS).

Criteria for ARDS

Berlin Definition of ARDS


Timing	Within one week of a known clinical insult or new or worsening respiratory symptoms.
Chest Imaging¹	Bilateral opacities — not fully explained by effusions, lobular/lung collapse, or nodules.
Origin of edema	Respiratory failure is not fully explained by cardiac failure or fluid overload. Need objective assessment (e.g., echocardiography) to exclude hydrostatic edema if no risk factors are present.
Oxygenation²	Mild: 200 mmHg < PaO2:FiO2 < 300 mmHg with PEEP or CPAP > 5 cm H2O3
	Moderate: 100 mmHg < PaO2:FiO2 < 200 mmHg with PEEP > 5 cm H2O
	Severe: PaO2:FiO2 < 100 mmHg with PEEP > 5 cm H2O

¹ Chest radiograph or computed tomography scan.

² If altitude is higher than 1000 m, the correct ion factor should be calculated as follows: [PaO2:FiO2 x (barometric pressure/ 760)].

³ This may be delivered noninvasively in the mild acute respiratory distress syndrome group.