Risk factors of ventilator-induced lung injury: mechanical power as surrogate of energy dissipation

Soon after physicians began to artificially ventilate patients with respiratory insufficiency due to poliomyelitis (1) and intensive care units developed, risks of mechanical ventilation—namely ventilator-induced lung injury (VILI)—became evident (2). The recognition of this iatrogenic, and potentially lethal, syndrome led to a slow change in the goal of mechanical ventilation for respiratory failure: from maintaining near-normal gas exchange, with use of large tidal volumes and high airway pressures (3), to avoiding additional lung damage—the so-called “lung protective” ventilation (4). The last 60 years of preclinical and clinical research in the field focused on identifying the single ventilator variable most responsible for VILI, with no conclusive answer.