Abstract
Acute lung injury is a disease with high mortality, which affects a large numbers of patients whose treatment continues to be debated. It has recently been postulated that hypercapnia can attenuate the inflammatory response during lung injury, which would assign it a specific role within lung protection strategies during mechanical ventilation. In this paper, we review current evidence on the role that high levels of CO(2) in the blood play in lung injury. We conclude that, although there are reports that show benefits, the most recent evidence suggests that hypercapnia can be harmful and can contribute to worsening lung damage.