What are the guidelines for managing Pediatric Acute Respiratory Distress Syndrome (PARDS) in the Pediatric Acute Lung Injury Consensus (PALIC)?

Pediatric Acute Respiratory Distress Syndrome (PARDS) Management Guidelines

For pediatric patients with PARDS, mechanical ventilation strategies should follow the Pediatric Acute Lung Injury Consensus Conference (PALICC) recommendations, using lung-protective ventilation with tidal volumes ≤10 mL/kg ideal body weight, appropriate PEEP titration, and oxygenation targets based on PEEP levels. 1

Ventilation Strategy

Ventilator Mode Selection

• Conventional Mechanical Ventilation (CMV) should be the first-line approach
• High-Frequency Oscillatory Ventilation (HFOV) may be considered if conventional ventilation fails 1
• High-Frequency Jet Ventilation (HFJV) should NOT be used in obstructive airway disease due to risk of dynamic hyperinflation 1
• Extracorporeal Membrane Oxygenation (ECMO) should be considered in reversible disease if conventional ventilation and/or HFOV fails 1

Setting Tidal Volume

• Target ≤10 mL/kg ideal body weight 1
• May need to be lower in lung hypoplasia syndromes 1
• Unlike adult ARDS guidelines that strictly recommend 4-8 mL/kg, pediatric data have not shown a single optimal Vt value associated with mortality outcomes

Setting Pressures

• Plateau Pressure (Pplat):
  • ≤28 cmH₂O in most cases
  • ≤29-32 cmH₂O if chest wall elastance is increased in restrictive disease
  • ≤30 cmH₂O in obstructive airway disease 1
• Driving Pressure: Keep <15 cmH₂O (Pplat minus PEEP)

Setting PEEP

• Basic PEEP: 5-8 cmH₂O for most patients 1
• PARDS-specific PEEP strategy:
  • Higher PEEP necessary based on disease severity
  • Consider PEEP titration and lung recruitment 1
  • For obstructive airway disease: add PEEP when air-trapping is present to facilitate triggering 1
  • For tracheo/bronchomalacia: use higher PEEP to stent airways open 1

Inspiratory Time/Respiratory Rate

• Set based on respiratory system mechanics and disease
• Use higher rates in restrictive disease to compensate for low tidal volumes 1
• Observe flow-time scalar to optimize settings

Oxygenation Targets

For PARDS specifically:

• SpO₂ 92-97% when PEEP <10 cmH₂O
• SpO₂ 88-92% when PEEP ≥10 cmH₂O 1

For other conditions:

• Healthy lungs: SpO₂ ≥95% on room air
• Cardiac patients: Individualized targets balancing pulmonary and systemic blood flow
• Pulmonary hypertension: May require FiO₂ up to 1.0 in acute crisis 1

Ventilation Targets

• Normal lungs: Target normal CO₂ (35-45 mmHg)
• PARDS: Permissive hypercapnia acceptable with pH >7.20 1
• Pulmonary hypertension: Maintain normal pH 1

Monitoring Parameters

• Blood gases: Measure PCO₂ in arterial or capillary samples
• Continuous monitoring:
  • SpO₂ in all ventilated children
  • End-tidal CO₂ in all ventilated children
  • Consider transcutaneous CO₂ monitoring 1
• Hemodynamic monitoring:
  • Measure pH, lactate, and central venous saturation in moderate-to-severe disease
  • Central venous saturation as marker for cardiac output 1
• Ventilator parameters:
  • Peak inspiratory pressure and/or plateau pressure
  • Mean airway pressure
  • PEEP
  • Consider measuring transpulmonary pressure, compliance, intrinsic PEEP 1
  • Monitor pressure-time and flow-time scalars 1

Supportive Measures

Positioning

• Maintain head of bed elevated 30-45° 1
• Consider prone positioning in severe cases

Airway Management

• Use cuffed endotracheal tube with cuff pressure ≤20 cmH₂O
• Use double-limb circuits for invasive ventilation
• Minimize dead space by added components 1
• Use humidification
• Perform endotracheal suctioning only when indicated, not routinely 1

Sedation and Neuromuscular Blockade

• Target patient-ventilator synchrony
• Consider neuromuscular blockade in severe cases requiring high ventilator settings 1
• Use caution with sedation/relaxation in cardiac dysfunction 1

Weaning and Extubation

• Start weaning as soon as possible
• Perform daily extubation readiness testing
• Consider non-invasive ventilation in neuromuscular patients 1
• Use steroids in patients at increased risk for post-extubation stridor 1

Non-invasive Respiratory Support Options

• CPAP: Consider in mixed disease and mild-to-moderate cardiorespiratory failure
• HFNC: Consider in mild-to-moderate disease, but not severe disease 1
• Both should not delay intubation when needed

Special Considerations

Cardiac Patients

• Same principles apply as for non-cardiac children
• Titrate ventilator settings more carefully
• Balance between pulmonary and systemic blood flow is crucial 1

Neuromuscular Disease

• Consider cough-assist devices
• Consider non-invasive ventilation post-extubation 1

Common Pitfalls to Avoid

1. Delayed recognition of PARDS leading to delayed intervention
2. Inappropriate ventilator settings (excessive tidal volumes, inadequate PEEP)
3. Routine practices without indication (e.g., routine suctioning, chest physiotherapy)
4. Delayed weaning from mechanical ventilation
5. Using home ventilators during the acute phase in the ICU 1
6. Routine hand ventilation unless specific conditions dictate otherwise 1

By following these guidelines, clinicians can optimize the management of pediatric patients with PARDS, potentially improving morbidity, mortality, and quality of life outcomes.