What are the maximum inspiratory pressure, pressure support, maximum pressure, and Positive End-Expiratory Pressure (PEEP) permissible during mechanical ventilation of a 1-month-old infant?

Maximum Ventilator Parameters for Mechanical Ventilation in a 1-Month-Old Infant

For a 1-month-old infant on mechanical ventilation, the maximum inspiratory pressure should be kept ≤28 cmH2O for healthy lungs, ≤29-32 cmH2O with increased chest wall elastance, and ≤30 cmH2O in obstructive airway disease. 1

Maximum Pressure Parameters

Peak Inspiratory Pressure (PIP)

• Maximum PIP should be kept ≤28 cmH2O for infants with healthy lungs 1
• For infants with increased chest wall elastance, PIP can be increased to ≤29-32 cmH2O 1
• In obstructive airway disease, PIP should be kept ≤30 cmH2O 1
• If pressure is being monitored during initial ventilation, an initial inflation pressure of 20 cmH2O may be effective in preterm infants, but pressures of 30-40 cmH2O may occasionally be necessary in term infants 1

Pressure Support (PS)

• Maximum pressure support should be kept ≤10 cmH2O for healthy lungs 1
• For disease conditions, optimal pressure support levels are not well established 1
• When setting pressure support, rise time should be set at 0.1-0.2 seconds to provide smooth pressure delivery without causing flow starvation 2

Maximum Pressure

• The absolute maximum pressure (including PIP and any additional pressure) should not exceed 28-32 cmH2O in most cases 1
• Monitoring plateau pressure is essential, with a suggested upper limit of 25-30 cmH2O to prevent dynamic hyperinflation 3
• High peak inflation pressures for even a few minutes can cause lung injury, impaired gas exchange, and reduced lung compliance 1

PEEP Settings

• Standard PEEP for infants should be 5-8 cmH2O 1
• Higher PEEP may be necessary depending on underlying disease severity (including in cardiac patients) 1
• For healthy lungs, PEEP should be kept ≤10 cmH2O 1
• PEEP titration and lung recruitment should be considered based on disease condition 1
• In obstructive airway disease, additional PEEP may be needed when there is air-trapping to facilitate triggering 1
• High levels of PEEP (8-12 cmH2O) may reduce pulmonary blood flow and increase risk of pneumothorax 1

Monitoring Considerations

• Measure peak inspiratory pressure, plateau pressure, mean airway pressure, and PEEP 1
• Monitor pressure-time and flow-time scalars to assess patient-ventilator interaction 1, 2
• Measure flow near the Y-piece of the patient circuit for children <10 kg to improve trigger sensitivity 1, 2
• Target patient-ventilator synchrony as a primary goal during ventilation 1, 2
• Set the inspiratory trigger sensitivity at 0.5-0.6 L/min to optimize patient-ventilator synchrony while avoiding auto-triggering 2

Common Pitfalls to Avoid

• Using unnecessarily high pressures when lower pressures would achieve adequate ventilation 1
• Failing to adjust PEEP based on underlying disease condition 1
• Setting inappropriate trigger sensitivity that can increase work of breathing or cause auto-triggering 2
• Not recognizing that FRC in ventilated infants with restrictive lung disease is significantly lower than normal, potentially requiring higher PEEP than clinically chosen in many cases 4
• Failing to monitor for patient-ventilator asynchrony, which can increase work of breathing 2