Figure 3: Links between Hypoxia and Inflammation.
Inflammed tissue (red) lesions are profoundly hypoxic, and hypoxia (blue) is a proinflammatory stimulus. Limited cellular oxygen availability results in the accumulation of cytotoxic metabolites, causing tissue damage and necrosis. Inflammation causes localized hypoxia by increased metabolic activity and oxygen (O2) consumption by immune and tissue cells. In addition, activated endothelial cells promote platelet aggregation and microthrombosis, thereby reducing oxygen supply. Examples for clinical condition primarily characterized by tissue hypoxia that causes inflammatory changes are summarized in the left panel, and perioperative inflammatory manifestations leading to tissue hypoxia on the right.