Hyperaemia
（重定向自Active hyperemia）
Hyperaemia or hyperemia is the increase of blood flow to different tissues in the body. It can have medical implications, but is also a regulatory response, allowing change in blood supply to different tissues through vasodilation. Clinically, hyperaemia in tissues manifest as erythema, because of the engorgement of vessels with oxygenated blood. Hyperaemia can also occur due to a fall in atmospheric pressure outside the body.