Methods to prevent ventilator-associated lung injury: a summary.

Mechanical ventilation can cause ventilator-associated lung injury (VALI). This may manifest itself in various forms such as pneumothorax or, at the most extreme level, multi-system organ failure. The exact mechanisms by which the injury occurs are not known but appear to involve the conversion of mechanical stimulation of alveolar membranes into intracellular signalling, with subsequent upregulation of inflammatory mediators that produce the damage. This has been termed biotrauma. Furthermore, disruption of alveolar-capillary membranes may allow the release of these mediators into the systemic circulation that underpins the systemic inflammatory response syndrome. Various protective ventilatory strategies may be employed in order to reduce the lung damage and shall be discussed in this paper.