ARDS Management Protocol
Based on Berlin Definition, Global ARDS 2023, ATS 2024 & SCCM Guidelines
Core Principle
ARDS management is not about making the saturation look nice. It is about oxygenating the patient while preventing further lung injury (VILI).
Berlin Definition (2012)
TimingWithin 1 week of known insult or worsening respiratory symptoms
ImagingBilateral opacities not fully explained by effusion, collapse, or nodules
Origin of edemaNot fully explained by cardiac failure or fluid overload
OxygenationPaO₂/FiO₂ with PEEP/CPAP ≥5 — Mild ≤300, Moderate ≤200, Severe ≤100
Global ARDS Definition 2023 — Resource-Limited Settings
Allows diagnosis using:
- HFNO ≥30 L/min
- SpO₂/FiO₂ <315 when SpO₂ is <97%
- Lung ultrasound (B-lines bilaterally)
- Does NOT require ABG, specific oxygen device, or PEEP
- PaO₂/FiO₂ <300 or SpO₂/FiO₂ <315
Do NOT wait for a perfect ABG before recognizing ARDS in district/referral settings.
Not Every White CXR is ARDS — Always Exclude:
Pulmonary edema / fluid overload
Massive pneumonia
Atelectasis
Pulmonary embolism
Raised intra-abdominal pressure
Obesity worsening mechanics
Primary ARDS (Direct)
- Pneumonia
- Aspiration
- Inhalational injury
- Pulmonary contusion
- Near drowning
Secondary ARDS (Indirect)
- Sepsis
- Pancreatitis
- Major trauma
- Massive transfusion
- Burns
- Severe shock
Mental Model: 3-Component Framework
If oxygenation is bad, do NOT automatically increase FiO₂ and PEEP. Ask:
Blood vesselsPE, microthrombosis, pulmonary hypertension, RV strain
AlveoliPneumonitis, edema, collapse, VILI
Chest wallObesity, abdominal hypertension, ascites, pregnancy