What is the recommended ventilation mode for a Maquet (Mechanical Ventilator)?

Recommended Ventilation Mode for Maquet Ventilators

For patients requiring mechanical ventilation on a Maquet ventilator, use volume-controlled ventilation (VCV) with low tidal volumes (4-8 mL/kg predicted body weight) as the primary mode, or alternatively use pressure-controlled ventilation (PCV) with plateau pressure limits ≤30 cm H₂O, particularly for patients with ARDS or at risk for ventilator-induced lung injury. 1

Mode Selection Algorithm

For ARDS Patients

• Strongly recommend volume-controlled mode targeting 4-8 mL/kg predicted body weight with plateau pressures maintained ≤30 cm H₂O 1
• Apply PEEP of 5-8 cm H₂O minimum, with higher PEEP (conditionally recommended) for moderate-to-severe ARDS 1
• For severe ARDS (PaO₂/FiO₂ <150), add prone positioning >12 hours daily 1
• Strongly avoid high-frequency oscillatory ventilation in moderate or severe ARDS 1

For Non-ARDS Respiratory Failure

• Use lower tidal volumes (weak recommendation for sepsis-induced respiratory failure without ARDS) 1
• Pressure support mode can be used for spontaneously breathing patients with variable respiratory demand 2, 3

For Weaning/Spontaneous Breathing

• SIMV (Synchronized Intermittent Mandatory Ventilation) is preferable to pressure support alone for patients at risk of hypoventilation or central apneas, as it provides a backup respiratory rate 4
• Pressure support mode may offer lower work of breathing for patients with increased respiratory demand 2, 3

Critical Technical Considerations for Maquet Ventilators

Volume Delivery Accuracy

• Important caveat: A 2015 bench study found that the Maquet SERVO-i's demand valve can allow patients to exceed set tidal volumes during volume-controlled ventilation if inspiratory flow exceeds the set flowrate 5
• This demand valve feature can be turned OFF with the latest software upgrade to maintain strict tidal volume control 5
• When implementing lung-protective ventilation strategies, ensure the demand valve is deactivated to prevent inadvertent delivery of excessive tidal volumes 5

Circuit Compensation Issues

• A 2009 study on the Maquet Servo I found that with circuit compensation ON, the ventilator generally underestimates true-delivered tidal volume, while without compensation it overestimates 6
• The error is relatively greater in infants and small children 6
• Despite these discrepancies, agreement between displayed and actual tidal volume remains acceptable for clinical use 6

Mode-Specific Settings

Volume-Controlled Ventilation

• Set tidal volume: 4-8 mL/kg predicted body weight 1
• Monitor plateau pressure continuously, keeping ≤30 cm H₂O 1
• Set inspiratory flow at 60 L/min as baseline 5
• Respiratory rate: 20 breaths/min as starting point, adjust for pH >7.20 1

Pressure-Controlled Ventilation

• Offers automatic pressure limitation but requires vigilant tidal volume monitoring 3, 7
• Titrate inspiratory pressure to achieve target tidal volume of 4-8 mL/kg 3
• May provide better patient-ventilator synchrony in spontaneously breathing patients 3

Common Pitfalls to Avoid

• Do not rely solely on ventilator-displayed tidal volumes in small children (<15 kg) without considering the known measurement discrepancies 6
• Disable demand valve features when strict volume control is required for lung-protective ventilation 5
• Avoid assist-control modes with active demand features that allow tidal volume to exceed set limits in ARDS patients 5
• Do not use pressure support as sole mode in patients at risk for central apneas or hypoventilation; use SIMV instead 4

Monitoring Requirements

• Measure plateau pressure in all ARDS patients 1
• Monitor delivered tidal volume at the Y-piece in children <10 kg 1
• Maintain head of bed elevation 30-45 degrees to prevent ventilator-associated pneumonia 1
• Perform daily spontaneous breathing trials when weaning criteria are met 1