New Global Definition of ARDS (2024)

The new global definition of ARDS (Matthay and colleagues, AJRCCM 2024), the successor to the 2012 Berlin definition.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Category
Invasively ventilated. A minimum PEEP of 5 cm H2O is required for…
Criterion applying to ALL categories. An acute predisposing risk factor is present
Yes
Criterion applying to ALL categories. Edema is not exclusively or primarily…
Yes
Criterion applying to ALL categories. Onset or worsening of hypoxemic…
Yes
Criterion applying to ALL categories. Bilateral opacities on radiography or CT
Yes
INTUBATED ONLY
Yes
Which oxygenation ratio
PaO2:FiO2
The oxygenation ratio value
150 ratio

Result: severity moderate

The tool opens with these values already filled in. Replace them with your own.

What the result means

All categories
Risk factor; edema not primarily cardiogenic; within 1 week; bilateral opacities.
Nonintubated
HFNO 30 L/min or more, or NIV/CPAP 5 cm H2O or more. NO SEVERITY GRADE EXISTS here.
Intubated mild
PaO2:FiO2 above 200 to 300, or SpO2:FiO2 above 235 to 315. Needs PEEP 5 or more.
Intubated moderate
PaO2:FiO2 above 100 to 200, or SpO2:FiO2 above 148 to 235.
Intubated severe
PaO2:FiO2 100 or below, or SpO2:FiO2 148 or below.
Resource-limited
SpO2:FiO2 315 or below. NO PEEP or flow requirement, and NO severity grade. A different denominator.
SpO2 gate
The saturation ratio is INVALID above SpO2 97%. Do not compute it there.
Corrections
Estimated FiO2 = ambient + 0.03 x L/min. Above 1000 m, multiply the ratio by barometric pressure / 760.
Scope
A definition, not a severity score or prognostic model. Does not identify the cause or indicate any intervention.

What you enter

  • Category.
  • Criterion applying to ALL categories.
  • Criterion applying to ALL categories.
  • Criterion applying to ALL categories.
  • Criterion applying to ALL categories.
  • INTUBATED ONLY.
  • NONINTUBATED ONLY.
  • Which oxygenation ratio.
The other 2 fields
  • Category. Decides whether a severity grade exists at all: ONLY the intubated category is graded [nonintubated = On high-flow nasal oxygen at 30 L/min or more, or noninvasive ventilation or CPAP with at least 5 cm H2O end-expiratory pressure. intubated = Invasively ventilated. A minimum PEEP of 5 cm H2O is required for every severity category. resource-limited = Neither positive end-expiratory pressure nor a minimum oxygen flow rate is required, and only the saturation ratio is used.]
  • Criterion applying to ALL categories. An acute predisposing risk factor is present (pneumonia, nonpulmonary infection, trauma, transfusion, burn, aspiration, or shock)
  • Criterion applying to ALL categories. Edema is not exclusively or primarily attributable to cardiogenic pulmonary edema or fluid overload, and hypoxemia is not primarily attributable to atelectasis
  • Criterion applying to ALL categories. Onset or worsening of hypoxemic respiratory failure within 1 week of the risk factor or of new or worsening respiratory symptoms
  • Criterion applying to ALL categories. Bilateral opacities on radiography or CT, or bilateral B lines and/or consolidations on ultrasound, not fully explained by effusions, atelectasis, or nodules/masses
  • INTUBATED ONLY. Whether PEEP is at least 5 cm H2O. Required for EVERY intubated severity category; severity is not read off the ratio alone.
  • NONINTUBATED ONLY. Whether the patient is on high-flow nasal oxygen at 30 L/min or more, or NIV/CPAP with at least 5 cm H2O end-expiratory pressure.
  • Which oxygenation ratio. The resource-limited category accepts SpO2:FiO2 ONLY [pf = PaO2:FiO2; sf = SpO2:FiO2]
  • The oxygenation ratio value. Apply the altitude correction first if above 1,000 m.
  • Oxygen saturation. REQUIRED when using SpO2:FiO2, because the ratio is INVALID above 97 percent and the tool refuses to assess there.
How this is calculated

Matthay MA, Arabi Y, Arroliga AC, et al. A New Global Definition of Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med. 2024;209(1):37-47. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

Browse all tools

Built by Clay Good. Source on GitHub.