Neonatal and Pediatric Mechanical Ventilation: Essential Strategies

Posted on Sep 16, 2025 in Medicine & Health

Mechanical Ventilation Indications

Mechanical ventilation is indicated in various conditions, particularly in neonates and pediatric patients. Key indications include:

Apnea and Respiratory Failure

  • Apnea: Characterized by a PaO2 < 50 mmHg or PaCO2 > 65 mmHg.
  • Pulmonary Diseases: Respiratory Distress Syndrome (RDS), Persistent Pulmonary Hypertension of the Newborn (PPHN), Meconium Aspiration Syndrome (MAS), Pneumonia, Acute Respiratory Distress Syndrome (ARDS).
  • Neurological/Neuromuscular Conditions: Asphyxia, head trauma, spinal cord atrophy, muscular dystrophy.

Congenital Abnormalities

  • Congenital diaphragmatic hernia.
  • Congenital heart disease.
  • Post-thoracic surgery.

Ventilator Modes and Settings for Neonates and Children

Understanding the appropriate ventilator modes and settings is crucial for effective respiratory support in infants and children.

Common Ventilator Modes

The most commonly used ventilator modes in infants and children are Synchronized Intermittent Mandatory Ventilation (SIMV) and Pressure Support Ventilation (PSV). These can be either Pressure-Controlled Ventilation (PCV-SIMV) or Volume-Controlled Ventilation (VCV-SIMV).

  • PCV-SIMV: Frequently used in children when compliance is greatly reduced, such as in severe ARDS.
  • VCV-SIMV: More commonly used when lung compliance is essentially normal, as seen in some neuromuscular disorders.
  • PSV: Similar to PCV, PSV supports spontaneous breathing. The patient initiates or triggers the breath, which is then limited to a preset pressure. The breath is terminated or cycled when a percentage of the peak inspiratory flow is met. Tidal volume (Vt) and inspiratory time (Ti) will vary from breath to breath.

Combined modes can also be utilized, such as PCV-SIMV+PSV or VCV-SIMV+PSV.

Ventilator Settings

  • Peak Inspiratory Pressure (PIP): Higher than 25 cmH2O increases the risk of barotrauma. Common target Vt is considered when adjusting PIP. Target Vt values are typically 5-7 ml/kg in neonates and slightly higher, 6-8 ml/kg in children.
  • Tidal Volume (Vt): A delivered or target volume of 6 to 8 ml/kg is the general goal.
  • Ventilator Rate: In neonates, the goal is to keep the PaCO2 between 45 to 55 mmHg.
  • Inspiratory Time (Ti): As low as 0.3 seconds for neonates and as long as 1.0 second for older children. Ti is often set by adjusting peak flow with some ventilators.
  • Oxygen Concentration (FiO2): The lowest possible to maintain adequate oxygenation. For preterm infants, SpO2 targets are typically between 88% to 94%.
  • Positive End-Expiratory Pressure (PEEP): Commonly set between 5 to 8 cmH2O.
  • Mean Airway Pressure (Paw): When Paw exceeds 15 cmH2O, it is considered dangerous, and other strategies such as High-Frequency Ventilation (HFV) may be considered.

Noninvasive Positive Pressure Ventilation (NIPPV)

NIPPV is used to prevent intubation or manage post-extubation respiratory failure in conditions such as:

  • Pulmonary edema.
  • Neuromuscular diseases.
  • Sleep apnea.
  • COPD exacerbations.

Advanced Ventilatory Support

For patients requiring more intensive respiratory assistance, advanced strategies are available.

High-Frequency Ventilation (HFV)

HFV includes two primary types:

  • High-Frequency Jet Ventilation (HFJV): Uses rates of 100 to 600 per minute and extremely short inspiratory times (20-40 milliseconds).
  • High-Frequency Oscillatory Ventilation (HFOV): Employs frequencies up to 15 Hz (900 cycles per minute).

Weaning from HFV

Weaning from HFV typically begins when the FiO2 is equal to or less than 0.60. The Mean Airway Pressure (Paw) is slowly reduced. When Paw is less than 15 to 18 cmH2O, the patient may be trialed off HFV or transitioned to conventional ventilation.

HFV Strategies

Two main strategies are used in HFV:

  • High Volume Strategy (Recruitment): Used to restore and sustain Functional Residual Capacity (FRC) by increasing Paw until the critical opening pressure of the lung has been exceeded. Adequate FRC may be determined clinically by observing:
    • Incremental increases in SpO2.
    • Decrease in FiO2.
    • Optimal lung expansion on chest X-ray, showing the diaphragm at the eighth to ninth rib level.
  • Low Volume Strategy (Air Leak): Used to lower Paw to the point of resolution of an air leak. A higher FiO2 is often needed to maintain adequate oxygenation because FRC is maintained around, and not above, the critical opening pressure. This strategy is employed for profound and worsening air leaks.

Inhaled Nitric Oxide (iNO)

Inhaled Nitric Oxide is a selective pulmonary vasodilator used to treat newborns requiring mechanical ventilation for hypoxic respiratory failure. It improves oxygenation and reduces the need for Extracorporeal Membrane Oxygenation (ECMO).

  • Recommended iNO Dose: 20 parts per million (ppm).
  • Weaning iNO: Once a response has been achieved and sustained, the iNO dose is gradually reduced, typically 50% each step, to a final dose of 1 ppm, at which point the drug is discontinued.
  • During Withdrawal: The FiO2 is increased to minimize the reoccurrence of pulmonary hypertension.

Extracorporeal Membrane Oxygenation (ECMO)

ECMO provides temporary support for severe heart and/or lung failure.

  • Veno-Venous (VV) ECMO: Supports only lung function.
  • Veno-Arterial (VA) ECMO: Supports both lung and heart function.

ECMO Indications

ECMO is indicated to improve survival in newborns with hypoxic respiratory failure associated with:

  • Persistent Pulmonary Hypertension of the Newborn (PPHN).
  • Meconium Aspiration Syndrome (MAS).
  • Sepsis.
  • Respiratory Distress Syndrome (RDS).
  • Congenital Diaphragmatic Hernia (CDH).
  • Congestive heart failure (as a bridge to heart transplantation).
  • Resuscitative efforts and perioperative management of patients with complex congenital heart disease.