ABSTRACT
Evidence has accumulated over the past decade that although mechanical
ventilation has helped many patients with respiratory failure, it can also cause damage to the lungs, particularly during the course of the acute
respiratory distress syndrome (ARDS). The mortality rate of patients with
this syndrome remains high, generally exceeding 30% to 40%. A recent study by the ARDS Network (1) has demonstrated that patients subjected
to low tidal volume ventilation associated with positive end expiratory pres-
sure (PEEP) had a significantly lower mortality than patients receiving
higher tidal volumes. This indicated that the ventilatory strategy signifi-
cantly influenced mortality. In addition to direct lung injury and air leaks (2), mechanical ventilation is responsible for worsening acute lung injury
by triggering lung and systemic inflammation (3-6). This process is now
widely known as ventilator-induced lung injury (VILI) (4,7,8).
