Hyperemia definition of Hyperemia in the Free Online Encyclopedia.

hyperemia [‚hī·pə′rē·mē·ə]

(medicine)

An excess of blood within an organ or tissue caused by blood vessel dilation or impaired drainage, especially of the skin.

Hyperemia

also plethora, an excess of blood in a tissue or organ. One may distinguish arterial and venous hyperemia. Arterial (active) hyperemia arises as a result of increased blood flow in the arteries owing to increased tonus of the vasodilator nerves or decreased tonus of the vasoconstrictor nerves. Among its causes are increased sensitivity of the blood vessels to physiological stimuli or the influence of extraordinary stimuli (such as bacterial toxins, high temperature, and products of tissue decomposition); in humans psychogenic factors (such as shame and anger) play a large role. Arterial hyperemia is characterized by dilatation of the arteries in the hyperemized area, elevation of temperature in the area, acceleration of blood flow, and reddening (for example, hyperemia of the face). It is accompanied by intensification of metabolic processes in the tissues and promotes the regeneration of tissues. Hemorrhages may occur during arterial hyperemia if there are pathological changes in the blood vessels. Arterial hyperemia is induced for therapeutic purposes by means of mustard plasters and cupping glasses. Venous (passive, static) hyperemia occurs when the outflow of blood along the veins is obstructed as a result of pressure on the venous wall (cicatrix, tumor, varicose dilatation of the veins, or edema), while the inflow remains unchanged or when there is a weakening of cardiac activity. Venous hyperemia is characterized by deceleration of blood flow to the point of complete stasis. Oxygen deficit develops in the tissues, the vascular walls become more permeable, and edema develops. Prolonged blood stasis and edema may lead to atrophy of the parenchyma of an organ.

V. A. FROLOV

Mentioned in	?		References in periodicals archive	?		Encyclopedia browser	?		Full browser	?
No references found	Most adverse reactions with LACRISERT were mild and transient and included transient blurring of vision, ocular discomfort or irritation, matting or stickiness of eyelashes, photophobia, hypersensitivity, edema of the eyelids, and hyperemia. ATON PHARMA AQUIRES MARKETING RIGHTS TO MERCK'S TIMOPTIC LINE by Biotech Business Flow-mediated dilatation of the brachial artery was evaluated after reactive hyperemia induced by cuff obstruction of the forearm, using high-resolution ultasonography. Polyphenolic compounds from red grapes acutely improve endothelial ... by Life Extension assembles 15 chapters written by contributors from the US, Europe, and Asia specializing in functional magnetic resonance, electrophysiology, and optical imaging methods who explain the basic principles of their techniques and how they are used in brain imaging to understand functions such as neural activity, energy metabolism, blood flow, the structures of tissues, and functional hyperemia. Dynamic brain imaging; multi-modal methods and in vivo applications by SciTech Book News	HyperCard hyperchamaerrhine hypercharge hyperchlorhydria hypercholesteremia hyperchromatic hyperchromatism hyperchromic hyperchromic anemia hyperchromicity hypercircle method hypercoagulability hypercomplex number Hypercomplex Numbers hypercomplex system hyperconjugation hypercoracoid hypercorticism hypercube hyperdisk hyperdolichocephalic hyperdolichocranial hyperdynamic ileus hyperemesis hyperemesis gravedorium Hyperemia hyperergia hyperesthesia hypereuryene hypereutectic alloy hypereutectoid steel hyperfine enhanced nuclear cooling Hyperfine Structure hyperfocal distance hyperforming hyperfrequency waves Hyperfunction hypergammaglobulinemia hypergene hypergeometric differential equation hypergeometric distribution hypergeometric function Hypergeometric Functions Hypergeometric Series hypergiant star hyperglobulinemia hyperglycaemia Hyperglycemia hyperglycemic factor hyperglycemic glycogenolytic factor hyperglycinenemia	hyperdrive Hyperdrives Hyperdulia Hyperdulia Hyperduly hyperdynamia hyperdynamia Hyperdynamic circulation hyperdynamic endotoxemia hyperdynamic ileus hyperdynamic ileus hyperdynamic ileus hyperdynamic syndrome hyperechema Hyperechogenic Areas in the Thalamus and Basal Ganglia hyperechoic Hyperelastosis cutis hyperemesis hyperemesis hyperemesis Hyperemesis Education and Research hyperemesis gravedorium hyperemesis gravidarum hyperemesis gravidarum hyperemesis gravidarum hyperemesis gravidarum hyperemesis lactentium hyperemesis lactentium hyperemesis lactentium Hyperemesis Research and Education Organization Hyperemia Hyperemia Unit hyperemic hyperemic hyperemic Hyperemic Average Peak Velocity Hyperemic Mean Transit Time hyperencephalus hyperencephaly hyperendemic hyperendemic disease hyperendemic disease hyperendemic disease hyperendemic disease hypereosinophilia hypereosinophilic syndrome hypereosinophilic syndrome hypereosinophilic syndrome hypereosinophilic syndrome hyperepinephrinemia hyperequilibrium hypererethism hyperergasia hyperergia hyperergia hyperergy hypererythrocythemia hypererythrocythemia hypererythrocythemia hyperesophoria hyperesthesia

Mentioned in

References in periodicals archive

Encyclopedia browser

Full browser

No references found

Most adverse reactions with LACRISERT were mild and transient and included transient blurring of vision, ocular discomfort or irritation, matting or stickiness of eyelashes, photophobia, hypersensitivity, edema of the eyelids, and hyperemia.

ATON PHARMA AQUIRES MARKETING RIGHTS TO MERCK'S TIMOPTIC LINE by Biotech Business

Flow-mediated dilatation of the brachial artery was evaluated after reactive hyperemia induced by cuff obstruction of the forearm, using high-resolution ultasonography.

Polyphenolic compounds from red grapes acutely improve endothelial ... by Life Extension

assembles 15 chapters written by contributors from the US, Europe, and Asia specializing in functional magnetic resonance, electrophysiology, and optical imaging methods who explain the basic principles of their techniques and how they are used in brain imaging to understand functions such as neural activity, energy metabolism, blood flow, the structures of tissues, and functional hyperemia.

Dynamic brain imaging; multi-modal methods and in vivo applications by SciTech Book News