From the Guidelines
Ventilator-induced lung injury (VILI) management should prioritize lung-protective ventilation strategies, including the use of low tidal volumes, appropriate positive end-expiratory pressure (PEEP), and prone positioning for patients with moderate-to-severe ARDS, as recommended by the most recent guidelines 1.
Key Strategies for VILI Management
- Low tidal volumes of 4-6 mL/kg of predicted body weight
- Maintaining plateau pressures below 30 cmH2O
- Applying appropriate PEEP typically between 5-15 cmH2O based on patient requirements
- Driving pressure (plateau pressure minus PEEP) should be kept below 15 cmH2O when possible
- Permissive hypercapnia may be necessary, allowing PaCO2 to rise while maintaining pH above 7.20
- Prone positioning for 16+ hours daily is recommended for patients with moderate-to-severe ARDS (P/F ratio <150) 1
Rationale and Benefits
The use of lung-protective ventilation strategies is supported by evidence from recent guidelines and studies, which demonstrate improved outcomes and reduced mortality in patients with ARDS 1. Prone positioning, in particular, has been shown to improve oxygenation and reduce ventilator-associated lung injury in patients with severe ARDS 1.
Implementation and Monitoring
Regular assessment of ventilator parameters and patient response is essential, with adjustments made to balance gas exchange needs against potential lung injury. This may involve the use of neuromuscular blockade with agents like cisatracurium (37.5 mg/hr infusion) for 48 hours in severe cases to improve ventilator synchrony. By prioritizing lung-protective ventilation strategies and prone positioning, clinicians can minimize the risk of VILI and improve outcomes for patients with ARDS.
From the Research
VILI Management Strategies
To manage ventilator-induced lung injury (VILI), several strategies can be employed, including:
- Minimizing inspiratory and expiratory stress, dynamic and static strain, energy, mechanical power, and intensity 2
- Using low tidal volume values and high positive-end expiratory pressure (PEEP) to reduce volutrauma 3
- Prone positioning to reduce lung damage and improve survival in patients with moderate to severe ARDS 2, 4
- Considering extracorporeal support in selected cases 2
- Balancing the risk of lung injury with untoward side effects from preventive efforts, and targeting prevention strategies to subsets of patients at increased risk 5
Mechanisms of VILI
VILI can occur through several mechanisms, including:
- Volutrauma: overdistension of alveoli due to high tidal volumes or pressures 2, 3, 5
- Atelectrauma: repetitive opening and closing of alveoli during tidal breathing 2, 5
- Barotrauma: damage to lung tissue due to high pressures 5
- Biotrauma: release of inflammatory mediators in response to lung injury 5
- Shear strain: deformation of lung tissue due to differences in regional mechanics 5
Ventilation Parameters
Ventilation parameters that can contribute to VILI include:
- Tidal volume: high tidal volumes can lead to volutrauma 2, 3
- Respiratory rate: high respiratory rates can lead to increased dynamic strain 2
- Positive end-expiratory pressure (PEEP): high PEEP can lead to increased static strain, but can also help to prevent atelectrauma 2, 3
- Peak, plateau, driving, and transpulmonary pressures: high pressures can lead to barotrauma and volutrauma 2