Ventilator Modes
What does CPAP stand for?
Continuous Positive Airway Pressure
What condition causes low lung compliance in neonates?
Respiratory Distress Syndrome (RDS)
What PaCO₂ range is typically targeted in permissive hypercapnia?
45–60 mmHg
What air leak condition can occur due to overdistension?
Pneumothorax
What setting controls oxygenation the most?
FiO₂ and PEEP
What is the primary indication for switching a neonate from CMV to HFOV?
Failure of conventional ventilation to maintain adequate oxygenation or ventilation, especially in cases of severe RDS, air leak syndrome, or refractory hypercapnia/hypoxemia.
What neonatal ventilator mode provides breaths synchronized with infant effort?
Synchronized Intermittent Mandatory Ventilation (SIMV)
What is the primary cause of increased airway resistance in a preterm infant?
Small airway diameter
A pH of 7.28 and PaCO₂ of 55 suggests what condition?
Respiratory acidosis
What is air trapping, and how can it be managed?
Incomplete exhalation leads to hyperinflation; lower rate or increase expiratory time
What does increasing the rate on a ventilator do to CO₂ levels?
Decreases CO₂ (more ventilation)
What is a typical starting mean airway pressure (MAP) when initiating HFOV?
2–4 cmH₂O higher than the MAP used in CMV.
Name one advantage of HFOV over conventional ventilation.
Reduces risk of volutrauma/barotrauma due to small tidal volumes
True or False: Surfactant improves lung compliance.
True
What does an increased A–a gradient indicate in a neonate?
Impaired oxygenation/diffusion problem
What disorder is linked to high oxygen exposure in preemies?
Retinopathy of Prematurity
What is a typical starting rate (breaths/min) for neonatal ventilation?
40–60 breaths per minute
What frequency range (Hz) is commonly used to start HFOV in neonates?
10–15 Hz.
What is the primary mode used to deliver noninvasive positive pressure?
BiPAP or CPAP
Define airway resistance.
Resistance to airflow in the airways
What acid-base imbalance is associated with hypoventilation?
Respiratory acidosis
What is volutrauma, and how can it be prevented in neonates?
Lung injury from overdistension; prevent by using low tidal volumes
What does lowering the I:E ratio do?
Allows more time for exhalation
What setting primarily controls CO₂ elimination in HFOV?
Amplitude (ΔP) and frequency (Hz).
What is the main purpose of Volume Guarantee (VG) in neonatal ventilation?
To deliver consistent tidal volumes while limiting pressure
Define lung compliance.
Lung stretchability or volume change per pressure unit
In metabolic acidosis, what respiratory compensation would you expect?
Hyperventilation to blow off CO₂
What does PIE stand for in neonatal ventilation?
Pulmonary Interstitial Emphysema
What is a typical initial inspiratory pressure (PIP) setting for a term neonate in pressure control mode?
20–25 cmH₂O (adjusted based on chest rise and tidal volume)
What setting primarily controls oxygenation in HFOV?
Mean airway pressure (MAP) and FiO₂.
What is a key benefit of NAVA (Neurally Adjusted Ventilatory Assist)?
Synchronizes ventilation with the infant’s neural respiratory drive
What effect does surfactant deficiency have on alveolar surface tension?
Increases surface tension, leading to alveolar collapse
What blood gas change would you expect with increased dead space?
Increased PaCO₂ due to ineffective ventilation
What ventilator setting is most implicated in causing barotrauma?
High Peak Inspiratory Pressure (PIP)
What does increasing PEEP do to FRC and oxygenation?
Increases functional residual capacity (FRC) and improves oxygenation
What is the first adjustment to make if PaCO₂ is elevated while on HFOV?
Increase amplitude (ΔP) or decrease frequency.
Which mode delivers fixed-rate breaths regardless of patient effort?
Assist-Control (A/C) or Control Mandatory Ventilation (CMV)
What is the relationship between pressure and volume in low compliance lungs?
Higher pressure needed for small volume changes
What does a low PaO₂ with normal PaCO₂ suggest?
V/Q mismatch
What’s the result of inadequate humidification in ventilated neonates?
Mucus plugging, airway drying
What is the target tidal volume for neonatal ventilation?
4–6 mL/kg
What clinical signs indicate that amplitude (ΔP) is set too low?
Inadequate chest wiggle and rising CO₂ levels.
What does HFOV stand for?
High-Frequency Oscillatory Ventilation
How does fluid in the lungs affect compliance?
Decreases compliance
What does base excess reflect?
Metabolic status or buffering capacity
What type of lung injury can result from consistently high peak inspiratory pressures (PIP) during mechanical ventilation?
Barotrauma – damage caused by overdistension and rupture of alveoli
What is a typical initial inspiratory time (Ti) setting for a neonate?
0.3–0.5 seconds
When initiating HFOV, what is a safe starting amplitude setting (ΔP)?
Typically 20–30 cmH₂O, titrated to achieve visible chest wiggle to the umbilicus.
Which mode delivers mandatory breaths at preset intervals without patient trigger?
Intermittent Mandatory Ventilation (IMV)
Why are preterm infants more prone to atelectasis?
Due to immature lungs, decreased surfactant, and poor compliance
What is the normal pH range for neonates?
7.25–7.35
What is bronchopulmonary dysplasia (BPD)?
Chronic lung disease from prolonged ventilation and oxygen therapy
What settings affects minute ventilation the most?
Rate and tidal volume
What should you assess to confirm that HFOV is delivering adequate ventilation besides chest wiggle?
Monitor PaCO₂ trends on blood gases and observe chest wall movement extending from the clavicles to the mid-abdomen.
Which ventilator mode adjusts pressure support based on neural drive?
NAVA (Neurally Adjusted Ventilatory Assist)
What structural feature helps maintain airway patency?
Cartilage rings and smooth muscle
What gas exchange abnormality is seen in severe RDS?
Hypoxemia with or without hypercapnia
What complication can occur due to aggressive ventilation and leads to cyst-like air collections in the lungs?
Pulmonary Interstitial Emphysema (PIE)
What is a typical starting FiO₂ setting for a term neonate in respiratory distress?
0.40–0.60 (adjusted based on SpO₂ targets)
What oxygen index (OI) value is commonly used as a threshold to consider initiating HFOV in a neonate?
An OI > 15–20 is often used as a threshold to consider HFOV, indicating severe hypoxic respiratory failure.