What are the recommended ventilator settings during Cardiopulmonary Resuscitation (CPR)?

Ventilator Settings During CPR

For adult patients in cardiac arrest with an advanced airway, set the ventilator to: tidal volume 8 mL/kg, respiratory rate 10 breaths/minute, FiO₂ 100%, PEEP 0 cm H₂O, inspiratory-to-expiratory ratio 1:5, and peak pressure alarm at 60 cm H₂O. 1, 2

Core Ventilator Parameters

Tidal Volume and Oxygenation

• Set tidal volume at 8 mL/kg predicted body weight with FiO₂ 100% to ensure adequate oxygenation during the low-flow state of cardiac arrest 1, 2
• This is slightly higher than the 6-7 mL/kg used in standard mechanical ventilation, accounting for potential volume loss during chest compressions 1
• The 100% oxygen concentration is essential to maximize arterial oxyhemoglobin content and oxygen delivery during severely compromised circulation 1

Respiratory Rate

• Maintain a respiratory rate of exactly 10 breaths per minute (1 breath every 6 seconds) 1, 3, 2
• This rate minimizes the detrimental effects of positive-pressure ventilation on venous return and cardiac output 1
• Hyperventilation (>12 breaths/minute) significantly decreases survival by increasing intrathoracic pressure, reducing venous return, and diminishing cardiac output 1, 4
• Real-world data shows that hyperventilation is common during CPR, with median rates of 21 breaths/minute observed in practice—this must be actively avoided 4

PEEP Setting

• Set PEEP to 0 cm H₂O to allow maximal venous return to the heart during chest compressions 1, 2
• Positive-pressure ventilation significantly lowers cardiac output during CPR, making minimization of intrathoracic pressure essential 1
• Zero PEEP maximizes the pressure gradient for venous return between chest compressions 1

Inspiratory-to-Expiratory Ratio

• Use an I:E ratio of 1:5 to provide adequate inspiratory time (approximately 1 second) while maximizing expiratory time 1, 2
• This ratio minimizes mean airway pressure and allows adequate time for venous return between breaths 1
• The prolonged expiratory phase is critical for maintaining cardiac output during CPR 1

Peak Pressure Management

• Set the maximum peak inspiratory pressure (Pmax) alarm at 60 cm H₂O to allow adequate tidal volume delivery during chest compressions 2
• Chest compressions can significantly increase airway pressures, and this higher alarm threshold prevents premature ventilator cycling 2
• Studies document peak inspiratory pressures during manual ventilation reaching 60.6 cm H₂O (range 46-106 cm H₂O) during CPR 4

Additional Ventilator Adjustments

Trigger Settings

• Switch OFF the ventilator trigger to prevent inadvertent triggering by chest recoil during compressions 2
• Chest compressions can create pressure changes that may falsely trigger the ventilator, leading to asynchronous ventilation 2

Mode Selection

• Use volume control ventilation rather than pressure control to ensure consistent tidal volume delivery despite changing chest compliance during compressions 2
• Volume control mode guarantees the target tidal volume is delivered regardless of airway pressure fluctuations 2

Critical Pitfalls to Avoid

Hyperventilation

• The most common error is excessive respiratory rate, with studies showing rates of 21-41 breaths/minute in actual practice despite guideline recommendations of 10 breaths/minute 4
• Hyperventilation causes persistently high airway pressures (positive for 95% of the respiratory cycle), which severely impairs venous return and cardiac output 4
• Real-time monitoring of ventilation frequency is crucial to ensure adherence to the 10 breaths/minute target 1

Excessive Airway Pressure

• Avoid allowing mean airway pressure to remain elevated throughout the respiratory cycle, as this continuously impedes venous return 4
• The 1:5 I:E ratio specifically addresses this by minimizing the time spent at positive pressure 1

Using Actual vs. Predicted Body Weight

• Always calculate tidal volume using predicted body weight, not actual body weight, particularly in obese patients 5, 3
• Using actual weight in obese patients leads to excessive volumes and potential barotrauma 5

Pediatric Considerations

For pediatric patients, the evidence is less definitive, but ventilatory rates >10 breaths/minute may be reasonable, approaching age-appropriate respiratory rates while avoiding both hypoventilation and hyperventilation. 6

• The traditional adult-derived recommendation of 10 breaths/minute may cause hypoventilation in infants and children 6
• No specific pediatric ventilatory rate has been validated by high-quality evidence 6
• The 2024 International Consensus recommends using ventilatory rates close to age-appropriate respiratory rates as a good practice statement 6

Monitoring During CPR

• Continuously monitor delivered tidal volume and respiratory rate to ensure adherence to targets 1
• Consider capnography monitoring, though optimal targets during CPR remain undefined 6
• Visible chest rise remains an important clinical indicator of adequate ventilation 5