eTable 1. Longitudinal bronchoalveolar lavage findings in ARDS improvers vs. non-improvers
ARDS onset / Over Time
Nonsurvivors vs. survivors / Improvers
or survivors / Non improvers
or nonsurvivors
TNF-, IL-1, IL-6 / Higher [1, 2] / Decreased [1] / Increased [1]
IL-8a, Soluble intercellularadhesion molecule-1 / Higher [1, 3] / Decreased [1, 3] / Increased [1, 3]
IL-10 / Similar [4] / Unchanged / Decreased
Vascular endothelial growth factor b / Lower [5] / Higher [5] / Lower [5]
BAL total protein and albumin a / Similar [1] / Decreased [1] / Increased [1]
Neutrophilia (percentage) a / Similar [3, 6] / Decreased [3, 6] / Increased [3, 6]
Procollagen type I and/or III c / Increased [7, 8]
Similar [10] / Decreased [7-9] / Increased [7, 10, 11]
Keratinocyte growth factor (KGF) d / Higher [12]
Patients are classified based on physiological improvement over time or survival.
Higher or lower in comparison to the other group
a. BAL IL-8 levels correlated with BAL neutrophilia (r=0.56624, p=0.02) [3], and BAL protein concentration [13] .
b. Vascular endothelial growth factor (VEGF) is known to contribute to the development of pulmonary edema, and has been suggested to have a protective role against lung injury. VEGF levels in ELF were also inversely correlated with LIS.
c. In one study, BAL Procollagen type III level prior to lung biopsy highly correlated with the severity of lung fibroproliferation (p <0.01, Rho = 0.635) [11]
d. KGF, a member of the fibroblast growth factor family (also named FGF-7), is secreted primarily by fibroblasts and was shown to induce type II alveolar epithelial cells (AEC2) AEC2 proliferation [12].

eTable2. Pathologic features of diffuse alveolar damage (DAD)

Acute (< 72 hours) / Subacute (3 – 14 days) / Chronic (> 10 days)
Capillary congestion
Intra-alveolar hemorrhage
Pulmonary edema
Atelectasis
Hyaline membranes / Interstitial edema
Alveolar lining cell hyperplasia
Hyaline membranes / Epithelial hyperplasia
Interstitial fibrosis
Neutrophilic infiltrate
Intra-alveolar cellular debris / Mononuclear cell infiltrate
- Lymphocytes, plasma cells

eTable 3. Findings of Thoracic Ultrasonography

Finding / Definition / Clinical Implication
Normal Characteristics
Lung sliding / A regular rhythmic movement synchronized with respiration that occurs between the parietal and visceral pleura / No pneumothorax at point of transducer application.
A-lines / Repetitive horizontal artifacts occurring at a standardized distance from skin to pleural line / A-lines with concurrent lung sliding suggest normal aeration.
Abnormal Characteristics
B-lines / Discrete laser-like vertical hyperechoic reverberation artifacts that arise from the pleural line, extend to the bottom of the screen without fading, and move synchronously with lung sliding / Presence of B-lines excludes pneumothorax. Three or more B-lines in the intercostal space are suggestive of interstitial syndrome.
C (consolidation)-pattern / Subpleural echo-poor regions or one with tissue-like echotexture / Suggestive of infection, tumor, mass, or atelectatic lung
Pleural abnormality / Pleural thickening 3 mm, evidence of small subpleural consolidations, or coarse appearance of the pleural line / Commonly seen in pneumonia and ARDS but not in cardiogenic pulmonary edema

References

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