Evaluación crítica de la evidencia / Critical assessment of the evidence

ABSTRACT

The mechanism of barotrauma and volutrauma has been described since the 70s in patients with acute lung injury and acute respiratory distress syndrome receiving high tidal volume ventilation (10-15 ml/kg ideal body weight). This led to the development of controlled clinical trials in an attempt to determine the ideal tidal volume. Different forms of mechanical ventilation were proposed in the 90s using tidal volumes ranging between 3-12 ml/kg of the estimated weight. However, it was only in 2000 when the ARMA study published by the ARDS Network provided recommendations for low-volume mechanical ventilation (6 ml/kg) and airway plateau pressures under 30 cm H2O, leading to a significant reduction in mortality, from 40% down to 31% in patients with ARDS. Since then, the protective ventilation strategy has been broadened to include other types of patients, including those taken to elective surgery, although not taking into consideration the large difference in the pathophysiology of ventilation between diseased and healthy lungs, or the different consequences. Despite this, some clinical trials have found the benefit of low tidal volume ventilation in terms of pulmonary infection and, mortality outcomes. However, other studies like ours have shown an increase in 30-day mortality.