ARDS Ventilator Management

Oxygenation

PaO₂

Use an ABG obtained on the current FiO₂.

mmHg

FiO₂

Enter as percent.

PEEP

Also used to calculate driving pressure.

cm H₂O

Lung-Protective Ventilation

Sex

Used only to calculate predicted body weight.

Height

PBW is based on height, not actual weight.

Add respiratory mechanics

Current tidal volume

Used to compare with the 6 mL/kg PBW goal.

Plateau pressure

Measure with an inspiratory hold when passive.

cm H₂O

Bedside interpretation

Enter PaO₂ + FiO₂

The calculator updates automatically.

>300
Not ARDS range

201–300
Mild

101–200
Moderate

≤100
Severe

P/F ratio —

PBW —

Vt at 6 mL/kg —

Driving pressure —

Start with lung-protective ventilation and reassess oxygenation after stabilization.

Next steps

Enter values to generate severity-specific recommendations.

Ventilator targets

Vt ~6 mL/kg PBW
Pplat ≤30 cm H₂O

P/F severity describes the oxygenation component of ARDS and should be interpreted with the complete clinical definition.

Diagnosis

TimingAcute onset or worsening respiratory failure within ~1 week of a known insult or new/worsening symptoms.

ImagingBilateral opacities not fully explained by effusions, lobar collapse, nodules or masses. CXR, CT, or lung US can support the global definition.

OriginRespiratory failure not fully explained by cardiogenic pulmonary edema or fluid overload. ARDS and cardiac dysfunction can coexist.

HypoxemiaP/F ≤300. Conventional intubated severity: mild 201–300, moderate 101–200, severe ≤100.

2024 Global Definition: expands ARDS recognition to HFNO ≥30 L/min and allows S/F ≤315 when SpO₂ ≤97%; ultrasound can satisfy the imaging criterion. [1]

Common triggers: pneumonia, sepsis, aspiration, pancreatitis, major trauma, transfusion, inhalational injury, drowning and severe shock. Look for the trigger while simultaneously excluding dominant cardiogenic edema, focal collapse, PE and other ARDS mimics.

Initial Ventilator Strategy

Tidal Volume

6 mL/kg PBW

Adjust 4–8 mL/kg as needed

PBW, not actual body weight

Plateau Pressure

≤30 cm H₂O

Measure with inspiratory hold

If high, reduce Vt toward 4 mL/kg

Oxygenation

PaO₂ 55–80

SpO₂ 88–95%

Use PEEP/FiO₂ pairing

Driving Pressure

ΔP = Pplat − PEEP

Try to minimize; ≤15 is a common physiologic target

Association, not a formal RCT threshold

Low-Vt ventilation reduced mortality from 39.8% to 31.0% in ARMA. [2] Driving pressure was strongly associated with survival in pooled trial data. [3]

ARDSNet Lower PEEP / Higher FiO₂ Table

FiO₂	0.30	0.40	0.40	0.50	0.50	0.60	0.70	0.70	0.70	0.80	0.90	0.90	0.90	1.00
PEEP	5	5	8	8	10	10	10	12	14	14	14	16	18	18–24

ARDSNet Higher PEEP / Lower FiO₂ Table

FiO₂	0.30	0.30	0.30	0.30	0.30	0.40	0.40	0.50	0.50	0.50–0.80	0.80	0.90	1.00	1.00
PEEP	5	8	10	12	14	14	16	16	18	20	22	22	22	24

Moderate–severe ARDS: ATS 2024 conditionally favors higher PEEP without prolonged recruitment maneuvers. Prolonged recruitment maneuvers are recommended against. [4]

Escalation by Severity

Mild

P/F 201–300

Low-Vt ventilation
Pplat ≤30
PEEP/FiO₂ table
Treat trigger
Conservative fluid strategy after shock resolves

Proning is not routinely triggered by this severity range alone.

Moderate

P/F 101–200

All lung-protective measures
Favor higher PEEP if tolerated
If P/F <150: prone ≥16 h/session
Consider corticosteroids
NMBA only when needed for severe dyssynchrony/proning or early severe disease

ATS 2024: higher PEEP, corticosteroids and selected NMBA use are conditional recommendations. [4]

Severe

P/F ≤100

Prone early ≥16 h/session
Higher PEEP strategy if appropriate
Strict Pplat / Vt control
Correct dyssynchrony; consider short NMBA course
Early ECMO-center discussion if refractory

EOLIA entry thresholds included P/F <50 for >3 h, P/F <80 for >6 h, or pH <7.25 with PaCO₂ ≥60 for >6 h despite optimization. [10]

Proning

When to prone

After stabilization on low-Vt ventilation and adjusted PEEP, P/F remains <150
Start early after intubation when criteria persist
Use ≥16 consecutive hours per session
Continue daily while the physiology remains severe and no contraindication outweighs benefit
Proning is a mortality intervention, not just an oxygenation maneuver

16.0% vs 32.8%

PROSEVA 28-day mortality

Prone

16.0

Supine

32.8

Severe ARDS trial population: P/F <150, FiO₂ ≥0.60, PEEP ≥5, Vt near 6 mL/kg PBW. [5]

Adjuncts

Conditional

Corticosteroids

ATS 2024 suggests corticosteroids for ARDS, but there is no single mandated drug, dose or duration across all phenotypes.

DEXA-ARDS used dexamethasone 20 mg IV daily ×5 days, then 10 mg daily ×5 days in established moderate–severe ARDS. [8]

Selective

Neuromuscular Blockade

Do not paralyze every ARDS patient. Consider early NMBA when needed for severe dyssynchrony, proning, refractory hypoxemia or inability to maintain lung-protective ventilation.

ROSE found no 90-day mortality benefit from routine early continuous cisatracurium versus lighter-sedation usual care. [7]

After shock

Conservative Fluids

Once perfusion is adequate and shock has resolved, avoid persistent positive fluid balance; diurese when clinically appropriate.

FACTT improved lung function and shortened duration of mechanical ventilation/ICU stay without a mortality benefit. [6]

Avoid routine use

Prolonged Recruitment Maneuvers

Do not routinely perform prolonged high-pressure recruitment maneuvers in moderate–severe ARDS.

ATS 2024 recommends against them; ART showed higher mortality with an aggressive recruitment + titrated PEEP strategy. [4] [9]

Bridge only

Inhaled Pulmonary Vasodilator

iNO or inhaled epoprostenol can transiently improve oxygenation or unload the RV. Use as a rescue bridge, not definitive ARDS therapy.

No established mortality benefit.

Rescue

VV-ECMO

Selected patients with severe, potentially reversible ARDS refractory to optimized lung-protective ventilation, PEEP and proning should be discussed early with an experienced ECMO center.

ATS 2024 conditionally supports VV-ECMO in selected severe ARDS. [4]

Refractory Hypoxemia

1. Verify mechanics

ETT/circuit, pneumothorax, mucus plug, derecruitment, new edema, position.

Recheck Pplat, PEEP, Vt and ABG.

→

2. Optimize evidence-based care

Low Vt + Pplat ≤30

Higher PEEP if moderate–severe

Prone ≥16 h if P/F <150

NMBA if needed for synchrony

→

3. Rescue / ECMO discussion

Consider inhaled vasodilator as bridge.

Call ECMO center early if refractory and reversible.

EOLIA: P/F <50 >3 h, P/F <80 >6 h, or pH <7.25 + PaCO₂ ≥60 >6 h despite optimized ventilation.

Do not wait for prolonged injurious ventilation before referral. ECMO candidacy depends on reversibility, duration of high-intensity ventilation, comorbidity, bleeding/neurologic risk, age/frailty and center expertise, not P/F alone. [10]

Daily Bedside Checklist

Vt / PBW~6 mL/kg; reduce toward 4 if Pplat high

Pplat / ΔPPplat ≤30; minimize driving pressure

P/F trajectoryTrend after changes in PEEP, FiO₂ and position

ProningP/F <150 after stabilization? Start/continue ≥16 h

Fluid balanceAfter shock resolves, avoid unnecessary positive balance

Sedation / NMBAUse the minimum needed to achieve lung protection

Cause controlAntimicrobials/source control/aspiration or other trigger

RV functionWatch for acute cor pulmonale, especially with severe hypoxemia/hypercapnia

De-escalateReduce FiO₂, sedation and support as physiology improves

Key Trials

ARMA6 mL/kg PBW + Pplat ≤30 reduced mortality versus traditional high-Vt ventilation. [2]

PROSEVAEarly proning ≥16 h/session markedly reduced mortality in severe ARDS. [5]

FACTTConservative fluid management improved lung outcomes and ventilator-free time without mortality benefit. [6]

ROSERoutine early continuous NMBA did not reduce 90-day mortality versus lighter-sedation usual care. [7]

DEXA-ARDSSupports corticosteroid use in established moderate–severe ARDS; ATS now conditionally recommends steroids. [8]

ARTAggressive recruitment maneuver + compliance-titrated PEEP increased mortality. [9]

EOLIADefined widely used physiologic thresholds for ECMO consideration in very severe ARDS. [10]

ATS 2024 / ESICM 2023Current framework for higher PEEP, steroids, prone positioning, NMBA selectivity and VV-ECMO. [4] [11]

References

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. doi:10.1164/rccm.202303-0558WS.
View Global ARDS Definition

Global ARDS Definition

Acute Respiratory Distress Syndrome Network. Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. N Engl J Med. 2000;342(18):1301-1308. doi:10.1056/NEJM200005043421801.
View ARDSNet trial

Low Tidal Volume Ventilation

Amato MBP, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med. 2015;372(8):747-755. doi:10.1056/NEJMsa1410639.
View study

Driving Pressure

Qadir N, Sahetya SK, Munshi L, et al. An update on management of adult patients with acute respiratory distress syndrome: an official American Thoracic Society clinical practice guideline. Am J Respir Crit Care Med. 2024;209(1):24-36. doi:10.1164/rccm.202311-2011ST.
View ATS guideline

Primary Guideline

Guérin C, Reignier J, Richard JC, et al. Prone positioning in severe acute respiratory distress syndrome. N Engl J Med. 2013;368(23):2159-2168. doi:10.1056/NEJMoa1214103.
View PROSEVA trial

PROSEVA / Proning

National Heart, Lung, and Blood Institute ARDS Clinical Trials Network. Comparison of two fluid-management strategies in acute lung injury. N Engl J Med. 2006;354(24):2564-2575. doi:10.1056/NEJMoa062200.
View FACTT trial

FACTT / Fluid Strategy

National Heart, Lung, and Blood Institute PETAL Clinical Trials Network. Early neuromuscular blockade in the acute respiratory distress syndrome. N Engl J Med. 2019;380(21):1997-2008. doi:10.1056/NEJMoa1901686.
View ROSE trial

ROSE / Neuromuscular Blockade

Villar J, Ferrando C, Martínez D, et al. Dexamethasone treatment for the acute respiratory distress syndrome: a multicentre, randomised controlled trial. Lancet Respir Med. 2020;8(3):267-276. doi:10.1016/S2213-2600(19)30417-5.
View DEXA-ARDS trial

DEXA-ARDS / Steroids

Writing Group for the Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial Investigators. Effect of lung recruitment and titrated positive end-expiratory pressure versus low PEEP on mortality in patients with acute respiratory distress syndrome. JAMA. 2017;318(14):1335-1345. doi:10.1001/jama.2017.14171.
View ART trial

ART / Recruitment Maneuvers

Combes A, Hajage D, Capellier G, et al. Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome. N Engl J Med. 2018;378(21):1965-1975. doi:10.1056/NEJMoa1800385.
View EOLIA trial

EOLIA / VV-ECMO

Grasselli G, Calfee CS, Camporota L, et al. ESICM guidelines on acute respiratory distress syndrome: definition, phenotyping and respiratory support strategies. Intensive Care Med. 2023;49:727-759. doi:10.1007/s00134-023-07050-7.
View ESICM guideline

ESICM Guideline

Brower RG, Lanken PN, MacIntyre N, et al. Higher versus lower positive end-expiratory pressures in patients with the acute respiratory distress syndrome. N Engl J Med. 2004;351(4):327-336. doi:10.1056/NEJMoa032193.
View ALVEOLI trial

ALVEOLI / PEEP