Neonatal Ventilator and Its Settings

Neonatal Ventilator and Its Settings: A Complete Guide for Clinicians

Mechanical ventilation is a lifesaving support for newborns with respiratory failure. The neonatal ventilator manages neonatal ventilation modes and fine-tunes neonatal ventilator settings to balance oxygenation and ventilation while protecting fragile lungs.

1. Understanding Neonatal Ventilation Modes

SIMV neonatal (Synchronized Intermittent Mandatory Ventilation)
Delivers set breaths per minute that are synchronized with spontaneous breaths, allowing the infant to breathe between mandatory breaths. Useful for weaning and infants with moderate effort.

AC ventilation neonatal (Assist Control or Patient-Triggered Ventilation)
Each spontaneous breath triggers support at preset pressure or volume; a backup rate ensures ventilation if the infant is apneic.
Flow‑cycled, patient-triggered mode that assists spontaneous breaths. The clinician sets PS between PIP and PEEP, typically 50‑75% of VT, and no backup rate unless combined with SIMV.

Volume Guarantee (VG)
Available with SIMV or AC, it targets a set tidal volume (VT). The ventilator automatically adjusts PIP to achieve the target VT—typically 4‑6 ml/kg in neonates

High-Frequency Ventilation (HFOV / HFJV)
Delivers extremely high rates (up to 900 breaths/min or 10–15 Hz) at very low VT (often less than dead space). HFOV uses oscillatory pressure around a constant mean airway pressure (MAP). Ideal for severe RDS, air leaks, pulmonary edema, or atelectasis.

NAVA (Neurally Adjusted Ventilatory Assist)
Uses diaphragm electrical activity (EAdi) to synchronize and proportionally support each breath—showing promise in reducing asynchrony and improving comfort

2. Initial Neonatal Ventilator Settings

For Conventional Mechanical Ventilation (CMV: SIMV or AC + VG + PS)

Typical initial settings for a neonate in moderate distress or RDS:

VT: 4–6 ml/kg (sometimes up to 7 ml/kg in term infants); adjust in 0.5 ml/kg increments depending on pCO₂/pH
Rate (RR): 30–60 breaths per minute; often set at 40 initially, increase if no spontaneous effort or high pCO₂
PIP: Usually 16–24 cm H₂O (15–20 cm H₂O for very low birth weight infants, up to 25 cm H₂O for near-term infants)
PEEP: 4–8 cm H₂O (typically start at 5–6 cm H₂O) to maintain FRC and oxygenation
Inspiratory Time (iT): 0.3–0.5 s (preterm lower at ~0.3, term at ~0.4–0.45 s); I:E typically 1:2 or 1:3, or equal in higher RR
FiO₂: Adjust to SpO₂ target of 88–92% for preterm; >94% for term infants
PS: When used, set at ~ (PIP–PEEP)/2, minimum 4–6 cm H₂O, to support spontaneous effort

For High-Frequency Oscillatory Ventilation (HFOV)

Used when conventional ventilation fails or lung protection is critical:

MAP: 10–16 cm H₂O (often 1–2 cm H₂O higher than on CMV)
Frequency: Typically 8–12 Hz (10 Hz common; up to ~15 Hz in extremely preterm)
Amplitude / Power: ~2 × MAP; increased until visible chest vibration and acceptable pCO₂
PEEP / MAP: Same as MAP for HFOV; bias flow kept as per device specs to maintain FRC and gas exchange
FiO₂: Titrate down as oxygenation improves

3. Titrating Settings: Oxygenation vs Ventilation

Oxygenation (PaO₂ / SpO₂) is managed via FiO₂ and PEEP. Raise PEEP before increasing FiO₂ to avoid oxygen toxicity; but watch for barotrauma or decreased cardiac output with excessive PEEP
Ventilation (PaCO₂) is adjusted through Rate (RR) and VT. Increasing either increases minute ventilation

Blood gases should be rechecked 15–30 minutes after any ventilator adjustment to guide further changes

4. Weaning Strategies

Gradually reduce FiO₂, PIP, RR, or VT, allowing the infant to take more spontaneous breaths.
Transition from CMV (e.g. SIMV + VG) to PSV + VG or PSV alone as tolerated
MMV (Mandatory Minute Ventilation) can aid in weaning—automatically adjusts mandatory breaths if spontaneous minute ventilation is inadequate and reduces ventilator exposure
Monitor for readiness to extubate and transition to noninvasive support (e.g. CPAP, NIPPV, nHFOV).

5. Advanced and Non-Invasive Modes

NIPPV (Non-Invasive Positive Pressure Ventilation) supports breathing via nasal prongs and synchronized breaths—reduces extubation failure and supports alveolar recruitment
nHFOV uses nasal high-frequency oscillation (5–8 Hz; 300–480 breaths/min) and offers improved CO₂ clearance vs CPAP
BiPAP provides dual-level PEEP with synchronized support—often more successful than CPAP alone in RDS

6. Risks & Monitoring

Complications of neonatal mechanical ventilation include pneumothorax, airway trauma, bronchopulmonary dysplasia (BPD), and ventilator-associated lung injury. Careful monitoring of chest movement, breath sounds, and blood gases is essential

Example Initial Settings Table for RDS (Term Preemie)

Parameter	Typical Starting Range
Mode	AC + VG / SIMV + VG + PS
Tidal Volume	4–6 ml/kg
Rate	40 bpm (30–60)
PIP	16–24 cm H₂O (adjust per compliance)
PEEP	5–6 cm H₂O
iT	0.3–0.45 s
FiO₂	Start ~40%; adjust per SpO₂ target
PS	(PIP–PEEP)/2, ~4–6 cm H₂O

Conclusion

The neonatal ventilator is an essential tool for managing neonatal respiratory failure. Mastery of neonatal ventilation modes—like SIMV, AC, PSV, VG, HFOV, and newer modalities like NAVA—is critical. Careful titration of neonatal ventilator settings such as PIP, PEEP, VT, RR, iT, and FiO₂, guided by blood gases and bedside assessment, enables a lung-protective strategy. With thoughtful adjustments and weaning protocols, clinicians can support neonates effectively while minimizing complications.

Read this:https://thehealthwale.com/