From the Guidelines
Lung protective ventilation is a mechanical ventilation strategy that should be used in all mechanically ventilated patients, utilizing lower tidal volumes of 4-6 mL/kg of predicted body weight and maintaining plateau pressures below 30 cmH2O, as recommended by the most recent evidence 1. This approach is designed to minimize ventilator-induced lung injury in patients with acute respiratory distress syndrome (ARDS) and other critical respiratory conditions. The use of lower tidal volumes, typically targeting 4-6 mL/kg, rather than traditional volumes of 10-15 mL/kg, has been shown to reduce mortality in ARDS patients 1. Key components of lung protective ventilation include:
- Lower tidal volumes of 4-6 mL/kg of predicted body weight
- Plateau pressures below 30 cmH2O
- Appropriate positive end-expiratory pressure (PEEP) typically between 5-15 cmH2O based on oxygen requirements
- Allowance for permissive hypercapnia (elevated CO2 levels) if necessary
- Driving pressure (plateau pressure minus PEEP) should be kept below 15 cmH2O when possible Implementation requires calculating the patient's predicted body weight based on height and gender, not actual weight, and careful monitoring of respiratory mechanics, oxygenation, and ventilation parameters 1. Lung protective ventilation has been shown to significantly reduce mortality in ARDS patients and is now considered standard of care for most mechanically ventilated patients, even those without ARDS 1. The benefits of lung protective ventilation include:
- Prevention of overdistension of alveoli (volutrauma)
- Reduction of the repetitive opening and closing of alveoli (atelectrauma)
- Decrease in inflammatory responses (biotrauma) By adopting a lung protective ventilation strategy, clinicians can improve outcomes for mechanically ventilated patients and reduce the risk of ventilator-induced lung injury 1.
From the Research
Definition of Lung Protective Ventilation
Lung protective ventilation refers to a ventilatory strategy that aims to minimize ventilator-induced lung injury (VILI) in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) [(2,3,4,5,6)]. This approach involves the use of smaller tidal volumes, lower peak airway pressures, and appropriate levels of positive end-expiratory pressure (PEEP) to promote alveolar recruitment and prevent overdistention.
Key Components of Lung Protective Ventilation
- Use of smaller-than-conventional tidal volumes (6 ml/kg of ideal body weight) to maintain peak transpulmonary pressure below the pressure associated with overdistention [(2,5)]
- Titration of PEEP to promote maximal alveolar recruitment and improve oxygenation [(2,5)]
- Avoidance of high inspiratory plateau pressures (> 30 cm H2O) to prevent lung overdistention 5
- Use of recruitment maneuvers, pressure-controlled modes, and neuromuscular blocking agents as adjuvants to mechanical ventilation in severely hypoxemic patients 5
Benefits of Lung Protective Ventilation
- Reduced morbidity and mortality in patients with ALI and ARDS [(2,3,5,6)]
- Decreased pulmonary complications, such as ventilator-associated lung injury 6
- Improved outcomes in patients with acute respiratory distress syndrome requiring ongoing ventilatory support 6
Challenges and Limitations of Lung Protective Ventilation
- Potential difficulties in implementing low tidal volume ventilation, such as respiratory acidosis [(3,4)]
- Need for careful titration of ventilatory parameters to individual patient characteristics, such as lung mechanics and gas exchange 2
- Risk of hematological complications associated with extracorporeal membrane oxygenation or extracorporeal carbon dioxide removal 4