What is the recommended ventilator management strategy for Acute Respiratory Distress Syndrome (ARDS)?

Ventilator Management of ARDS

Core Lung-Protective Ventilation Strategy

For all patients with ARDS, implement lung-protective mechanical ventilation with tidal volumes of 4-8 mL/kg predicted body weight (target 6 mL/kg) and maintain plateau pressures strictly below 30 cmH₂O. 1, 2

Tidal Volume and Pressure Targets

• Set tidal volume at 6 mL/kg predicted body weight with an acceptable range of 4-8 mL/kg PBW 1, 2, 3
• Calculate predicted body weight using: Males = 50 + 0.91 × [height (cm) - 152.4] kg; Females = 45.5 + 0.91 × [height (cm) - 152.4] kg 2, 3
• Never exceed 8 mL/kg PBW even if plateau pressures appear acceptable—both parameters must be optimized simultaneously 2, 3
• Maintain plateau pressure ≤30 cmH₂O as an absolute ceiling 1, 2, 3
• Target driving pressure (plateau pressure minus PEEP) ≤15 cmH₂O, as this predicts mortality better than tidal volume or plateau pressure alone 3
• Accept permissive hypercapnia as a consequence of lung protection, maintaining pH >7.20 2

PEEP Strategy: Titrate to Disease Severity

For moderate-to-severe ARDS (PaO₂/FiO₂ <200 mmHg), use higher PEEP (typically >10 cmH₂O); for mild ARDS (PaO₂/FiO₂ 200-300 mmHg), lower PEEP may be appropriate. 1, 2, 3

• Higher PEEP strategy reduces mortality in moderate-to-severe ARDS (adjusted RR 0.90) 3
• Monitor for barotrauma when using PEEP >10 cmH₂O 2
• In patients with cirrhosis or hemodynamic instability, use lower PEEP (<10 cmH₂O) for mild ARDS to avoid impairing venous return 2

Prone Positioning: Mandatory for Severe ARDS

For severe ARDS with PaO₂/FiO₂ <150 mmHg, implement prone positioning immediately for at least 12-16 hours daily—this is a strong recommendation that reduces mortality (RR 0.74). 1, 2, 3

• Duration matters: trials with >12 hours/day proning showed mortality benefit, while shorter durations did not 2
• Do not delay prone positioning in severe ARDS—early implementation improves outcomes 2

Neuromuscular Blockade: Early Use in Severe ARDS

For early severe ARDS with PaO₂/FiO₂ <150 mmHg, use neuromuscular blocking agents for up to 48 hours. 2, 3

• Administer as intermittent boluses rather than continuous infusion when possible 2
• Use continuous infusion only for persistent ventilator dyssynchrony, need for deep sedation, prone positioning, or persistently high plateau pressures 2

Corticosteroids: Recommended for ARDS

Administer systemic corticosteroids to mechanically ventilated patients with ARDS—this represents the most recent high-quality guideline recommendation. 2, 3

• This is a conditional recommendation with moderate certainty of evidence 2

Fluid Management: Conservative Strategy

Use a conservative fluid strategy in established ARDS without tissue hypoperfusion. 2, 3

• Conservative fluid management improves ventilator-free days without increasing non-pulmonary organ failures 2, 3

Oxygenation Targets

• Target SpO₂ of 88-95% to avoid hyperoxia while maintaining adequate oxygenation 2, 3
• Start supplemental oxygen if SpO₂ <92%, and definitely if <90% 2, 3
• Maintain SpO₂ no higher than 96% in acute hypoxemic respiratory failure 2

Interventions to AVOID

Do not use high-frequency oscillatory ventilation—this is strongly recommended against and associated with harm. 1, 2, 3

• Do not routinely use pulmonary artery catheters for ARDS management 2, 3
• Do not use β-2 agonists for ARDS treatment without bronchospasm 2, 3
• Do not use recruitment maneuvers routinely or for prolonged periods—these are associated with harm 2, 3
• Inhaled nitric oxide is not indicated for ARDS and has not demonstrated mortality benefit 4, 5

Rescue Therapies for Refractory Hypoxemia

For severe refractory ARDS despite optimized ventilation, proning, and rescue therapies, consider VV-ECMO in carefully selected patients at experienced centers. 2

• ECMO should only be considered in carefully selected patients due to resource-intensive nature 2

Common Pitfalls to Avoid

• Do not prioritize normocapnia over lung-protective ventilation—accept permissive hypercapnia as necessary 2
• Do not use tidal volumes >8 mL/kg PBW even if plateau pressures are acceptable—both parameters must be optimized 2, 3
• Do not delay prone positioning in severe ARDS—early implementation improves outcomes 2
• Do not apply higher PEEP indiscriminately—tailor to ARDS severity and hemodynamic tolerance 2, 3

Sedation and Weaning

• Minimize continuous or intermittent sedation, targeting specific titration endpoints 2, 3
• Use spontaneous breathing trials in patients ready for weaning 2, 3
• Implement a weaning protocol for patients who can tolerate weaning 2, 3