Lung protective ventilation

Learning objectives

Lung protective ventilation (LPV) is a ventilation strategy aiming to reduce pulmonary complications after mechanical ventilation
Perioperative lung injury is a spectrum of disease that includes inflammation, impaired gas exchange, radiographic abnormalities, and respiratory failure
It is reasonable to use LPV as the default ventilation strategy in all mechanically ventilated patients

Tidal volume of 6-8 mL/kg predicted body weight
Plateau pressures <30 cm H2O
Start positive end-expiratory pressure (PEEP) at 5 cm H2O
When performing recruitment maneuvers use:
- The lowest effective pressure
- The shortest effective time
- The least amount of breaths

Ventilator induced lung injury (VILI) occurs via:
- Volutrauma: high tidal volumes
- Barotrauma: high inspiratory pressures
- Atelectotrauma: repetitive and rapid opening of the alveoli
- Biotrauma:
  - Inflammatory damage
  - Apoptotic/fibroproliferative processes
  - The translocation of bacteria and pro-inflammatory mediators
VILI shares common pathophysiological features with acute respiratory distress syndrome (ARDS)
ARDS is caused by:
- Pneumonia, sepsis, or aspiration pneumonitis (in 85% of cases)
- Blood transfusion, hemorrhagic shock, burns, inhalation injury
- Surgical factors: trauma, retraction injury, cardiopulmonary bypass, and ischemia-reperfusion injury
VILI occurs most often in patients with predisposing factors for ARDS
In patients at risk for ARDS or with ARDS, LPV;
- Improves oxygenation and pulmonary physiology
- Reduces postoperative pulmonary complications
- Reduces the relative risk of death at day 28