sign or symptom hyperemia Hyperemia, Reactive The presence of an increased amount of blood in a body part or an organ leading to congestion or engorgement of blood vessels. Hyperemia can be due to increase of blood flow into the area (active or arterial), or due to obstruction of outflow of blood from the area (passive or venous). Hyperemias, Reactive Active Hyperemia MESH:D006940 Venous Congestion Passive Hyperemia Hyperemia, Passive ICD9:362.37 Tomasz Adamusiak MedDRA:10020619 Reactive Hyperemia Reactive Hyperemias The presence of an increased amount of blood in a part or organ; engorgement. NCIt:C50588 SNOMEDCT:30098003 Hyperemias Hyperemia, Active Venous Engorgement Engorgement, Venous Congestion, Venous Hyperemia, Arterial Arterial Hyperemia