Ventilator Settings for Children with Bronchial Asthma
Initial Ventilator Settings
- The ideal initial ventilator settings for a 10 kg child with bronchial asthma should include a pressure-controlled mode with peak inspiratory pressure ≤30 cmH2O, PEEP of 5-8 cmH2O, tidal volume ≤10 mL/kg, and patient-ventilator synchrony as primary goals 1, 2, 3, 4
Mode Selection
- Use pressure-controlled ventilation as the initial mode for obstructive airway disease 1, 3
- Target patient-ventilator synchrony to reduce work of breathing 2, 4
Pressure Settings
- Keep peak inspiratory pressure (PIP) ≤30 cmH2O for obstructive airway disease 2, 3, 5
- Set PEEP at 5-8 cmH2O as baseline 1, 4
- Add additional PEEP in obstructive airway disease when there is air-trapping to facilitate triggering 2, 3
Volume Settings
- Target tidal volume ≤10 mL/kg ideal body weight (approximately 100 mL for a 10 kg child) 2, 4
- Set inspiratory time based on respiratory system mechanics using time constant and flow-time scalar observation 2, 4
Rate and I:E Ratio
- Use lower respiratory rates to allow for complete exhalation and prevent air trapping 3, 4
- Set longer expiratory times (I:E ratio of 1:3 or greater) to accommodate prolonged expiration in asthma 2, 3
Oxygenation Targets
- Target SpO2 ≤97% for obstructive airway disease 1, 4
- Monitor SpO2 continuously in all ventilated children 2, 3
CO2 and pH Management
- Accept higher PCO2 levels (permissive hypercapnia) unless contraindicated 3, 4
- Target pH >7.20 rather than normal PCO2 2, 4
Monitoring Parameters
- Measure peak inspiratory pressure, plateau pressure, mean airway pressure, and PEEP 2, 4
- Monitor pressure-time and flow-time scalars to assess for air trapping 3, 4
Supportive Measures
- Use humidification 1, 4
- Maintain head of bed elevated 30-45° 3, 4
- Use cuffed endotracheal tube with cuff pressure ≤20 cmH2O 2, 4