Experimental models and emerging hypotheses for acute lung injury.

Acute lung injury (ALI) involves the activation of multiple pathways leading to lung injury, resolution, and repair. Exploration of the roles of individual pathways in humans and animal models has led to a greater understanding of the complexity of ALI and the links between ALI and systemic multiorgan failure. However, there is still no integrated understanding of the initiation, the progression, and the repair of ALI. A better understanding is needed of how pathways interact in the human ALI syndrome and how complementary treatments can be used to modify the onset, severity, and outcome of ALI in humans.