Fact-sheet: Adult respiratory distress syndrome
Updated on 04/20/2018 at 5:49 PM
View all RADEOS cases associated with this fact-sheet
Definition
Permeability pulmonary edema occurring following direct or indirect injury to the alveolar-capillary membrane
Associated with severe pulmonary inflammation and severe hypoxemia
- Estimated mortality of 40 to 50%.
- described in 1967 in American soldiers during the Vietnam War, victims of open polytrauma following gunshot wounds, who underwent emergency surgery and massive transfusion.
Clinical features
Diagnostic criteria:
- Acute respiratory failure evolving over one week or less
- Bilateral opacities visible on chest imaging
- Pulmonary edema not predominantly of hydrostatic origin (no cardiogenic cause).
- Hypoxemia defined from the PaO2/FIO2 ratio, where FIO2 is the fraction of inspired oxygen in the air delivered by the ventilator, which allows classification of ARDS into 3 stages: Mild: 200
- Moderate: 100
- Severe: PaO2/FIO2≤100 mmHg
- Moderate: 100
Radiography
- airspace opacities
- bilateral and asymmetric
CT
- Ground-glass opacities and areas of airspace consolidation
- Bilateral and asymmetric distribution +++
- Septal thickening with "crazy paving" pattern
- Mosaic perfusion pattern
- Pleural effusions
Classification
Etiologies:
- Direct pulmonary causes Bacterial pneumonia
- viral (CMV, influenza, VZV)
- fungal
- parasitic (Pneumocystosis)
- Aspiration near drowning, gastric fluid, smoke
- Fat embolism
- amniotic fluid embolism
- air embolism
- Infiltration lymphangitic carcinomatosis
- vasculitis
- Trauma
- Indirect pulmonary causes shock ischemia / reperfusion
- anoxia and reperfusion (cardiac arrest)
- polytrauma
- sepsis and related conditions peritonitis
- severe pancreatitis
- bowel necrosis
- massive transfusion and related conditions cardiopulmonary bypass
- Plasmapheresis
- Toxic agents
- Miscellaneous: eclampsia
- diabetic ketoacidosis
Differential diagnosis
To rule out first: cardiogenic pulmonary edema
