What is the management of pediatric Acute Respiratory Distress Syndrome (ARDS)?

Management of Pediatric Acute Respiratory Distress Syndrome (PARDS)

Initial Respiratory Support Strategy

Begin with lung-protective mechanical ventilation using tidal volumes of 4-8 mL/kg predicted body weight (not actual body weight) and maintain plateau pressures ≤30 cmH₂O as the foundation of PARDS management. 1, 2, 3

Non-Invasive Ventilation Considerations

• Consider a trial of non-invasive ventilation (NIV) or high-flow nasal cannula only in children without clear intubation indications who are responding to initial resuscitation 4, 5, 2
• Reassess the patient's condition carefully and frequently within 1 hour of NIV initiation 4
• Proceed immediately to intubation if deterioration occurs, FiO₂ exceeds 70%, or the patient shows signs of worsening respiratory distress 2
• NIV should not delay endotracheal intubation in moderate-to-severe PARDS 4

Critical pitfall: Adult studies demonstrate that NIV increases adverse outcomes in severe ARDS, making early recognition of NIV failure essential to avoid delayed intubation and worse outcomes 4

Lung-Protective Ventilation Parameters

Tidal Volume and Pressure Limits

• Set tidal volume at 4-8 mL/kg predicted body weight (not actual body weight, which is a common error) 1, 2, 6, 3
• Maintain plateau pressure ≤30 cmH₂O at all times to prevent barotrauma 1, 2, 3
• Accept permissive hypercapnia as long as pH remains acceptable 3

The evidence strongly supports these limits: a 2020 study demonstrated that implementation of a lung-protective protocol with these parameters was associated with decreased mortality (adjusted hazard ratio 0.37,95% CI 0.16-0.88) after adjusting for severity of illness 6. However, observational data reveal that over 25% of pediatric patients with ARDS are still ventilated with tidal volumes above 10 mL/kg in actual practice, highlighting the gap between knowledge and implementation 7, 8.

Positive End-Expiratory Pressure (PEEP) Strategy

• Use higher PEEP in moderate-to-severe PARDS, guided by the ARDS-network PEEP-to-FiO₂ grid 4, 5, 1, 2
• Monitor closely for adverse hemodynamic effects, which may be more prominent in children with septic shock 4, 5
• Consider PEEP levels greater than 15 cm H₂O in severe PARDS while monitoring oxygen delivery, respiratory system compliance, and hemodynamics 3

Important caveat: Observational data show that clinicians often limit PEEP at ~10 cm H₂O even as oxygenation worsens, which is lower than protocol recommendations 7. This represents a missed opportunity for optimization.

Recruitment Maneuvers

• If recruitment maneuvers are considered, use stepwise incremental and decremental PEEP titration rather than sustained inflation techniques 4
• Monitor all PARDS patients carefully for tolerance during recruitment maneuvers 4
• There is insufficient data to make a definitive recommendation for or against routine use 4

Oxygenation and Ventilation Targets

• Target SpO₂ 92-96% to avoid oxygen toxicity 2
• Target PaO₂ 70-90 mmHg 2
• Accept permissive hypercapnia and mild hypoxemia (SpO₂ as low as 88%) in the context of lung-protective ventilation 3, 8

Fluid Management

Implement conservative fluid management once respiratory status is stabilized to minimize pulmonary edema. 5, 1, 2

• Avoid excessive fluid administration, which worsens oxygenation, promotes right ventricular failure, and increases mortality 1, 2
• This is a critical but often overlooked component of PARDS management 5

Adjunctive Therapies for Severe PARDS

Prone Positioning

Implement prone positioning for at least 12 hours per day in children with severe PARDS. 4, 5, 1, 2

• This intervention has demonstrated significant mortality reduction in adult trials and is strongly recommended 5, 2
• The duration of at least 12 hours per day is emphasized in research trials 4, 5

Neuromuscular Blockade

Consider neuromuscular blockade for 24-48 hours after ARDS onset in severe PARDS to improve ventilator synchrony and reduce oxygen consumption. 4, 5, 1, 2

• The exact duration has not been definitively determined, but most data support 24-48 hours 4, 5
• This should be reserved for severe PARDS rather than used routinely 4, 1

Inhaled Nitric Oxide (iNO)

Do not use inhaled nitric oxide routinely in all children with PARDS. 4, 5, 1, 2

• Consider iNO only as rescue therapy for refractory hypoxemia after optimizing all other oxygenation strategies (high PEEP, prone positioning, neuromuscular blockade) 4, 5, 1, 2
• This represents a strong recommendation against routine use but allows for selective application in the most severe cases 4, 5

High-Frequency Oscillatory Ventilation (HFOV)

• No recommendation can be made for or against HFOV in sepsis-induced PARDS 4
• HFOV may be considered if conventional ventilation fails, using an open lung strategy 4
• Recent evidence suggests HFOV may not provide mortality benefit and could potentially cause harm in some populations 4

Monitoring Requirements

• Continuously monitor oxygen saturation, respiratory mechanics, and hemodynamics to promptly identify deterioration 2
• Assess right ventricular function via echocardiography, as RV failure significantly worsens outcomes 2
• Reassess oxygenation classification daily, as patients who rapidly resolve may not need aggressive lung-focused therapy 4

Ventilator Mode Selection

• No specific ventilator mode can be recommended based on outcome data 4
• Pressure control is most commonly used (60% in observational studies), followed by volume control (19%) and pressure-regulated volume control (18%) 7
• With restored respiratory drive, pressure support ventilation may be considered with appropriate sensitivity settings 4

Avoiding Common Pitfalls

• Do not use actual body weight for tidal volume calculations—always use predicted body weight 1, 2, 7
• Do not delay intubation in patients failing NIV—this is associated with worse outcomes 4
• Do not limit PEEP prematurely as oxygenation worsens—this is a common practice error 7
• Do not use etomidate for intubation in children with septic shock or sepsis-associated organ dysfunction 4
• Do not routinely use insulin to maintain glucose below 140 mg/dL (strong recommendation against) 4

Advanced Rescue Therapies

• Consider VV-ECMO only at centers with ECMO expertise for patients with severe ARDS failing conventional management, particularly those with potentially reversible disease 2