- /huy'peuh ten"sheuhn/, n. Pathol.1. decreased or lowered blood pressure.2. a disease or condition characterized by this symptom. Also called low blood pressure.[1890-95; HYPO- + TENSION]
* * *Condition in which blood pressure is abnormally low.It may result from reduced blood volume (e.g., from heavy bleeding or plasma loss after severe burns) or increased blood-vessel capacity (e.g., in syncope). Orthostatic hypotensiondrop in blood pressure on standingresults from failure of the reflexes that contract muscles and constrict blood vessels in the legs to offset gravity as one rises. Hypotension is also a factor in poliomyelitis, shock, and barbiturate poisoning.
* * *also called low blood pressurecondition in which the blood pressure is abnormally low, either because of reduced blood volume or because of increased blood-vessel capacity. Though not in itself an indication of ill health, it often accompanies disease.Extensive bleeding is an obvious cause of reduced blood volume that leads to hypotension. There are other possible causes. A person who has suffered an extensive burn loses blood plasma—blood minus the red and white blood cells and the platelets. Blood volume is reduced in a number of conditions involving loss of salt and water from the tissues—as in excessive sweating and diarrhea—and its replacement with water from the blood. Loss of water from the blood to the tissues may result from exposure to cold temperatures. Also, a person who remains standing for as long as one-half hour may temporarily lose as much as 15 percent of the blood water into the tissues of the legs.Orthostatic hypotension—low blood pressure upon standing up—seems to stem from a failure in the autonomic nervous system. Normally, when a person stands up, there is a reflex constriction of the small arteries and veins to offset the effects of gravity. Hypotension from an increase in the capacity of the blood vessels is a factor in fainting (see syncope). Hypotension is also a factor in poliomyelitis (polio), in shock, and in overdose of depressant drugs, such as barbiturates (barbiturate).
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hypotension — [ ipotɑ̃sjɔ̃ ] n. f. • 1895; de hypo et tension ♦ Méd. Tension artérielle inférieure à la normale; diminution de la tension. Souffrir d hypotension. ⊗ CONTR. Hypertension. ● hypotension nom féminin Hypotension artérielle, diminution pathologique… … Encyclopédie Universelle
Hypotension — artérielle L hypotension artérielle correspond à une pression artérielle systolique inférieure à 90 mmHg (le chiffre le plus élevé des deux lorsque l on prend la pression artérielle). Il existe différentes sortes d hypotension: l hypotension … Wikipédia en Français
hypotension — ► NOUN ▪ abnormally low blood pressure. DERIVATIVES hypotensive adjective … English terms dictionary
hypotension — [hī′pō ten΄shən] n. abnormally low blood pressure hypotensive adj … English World dictionary
Hypotension — In physiology and medicine, hypotension refers to an abnormally low blood pressure. This is best understood as a physiologic state, rather than a disease. It is often associated with shock, though not necessarily indicative of it. Hypotension is… … Wikipedia
Hypotension — Als Hypotonie oder auch Hypotension (aus dem Griechischen) wird in der Medizin eine Spannung oder ein Druck unterhalb der Norm bezeichnet. Hypotonie gibt es z. B. des Muskeltonus, der Gehirnflüssigkeit (zerebrale H.), des Augeninnendruckes (H.… … Deutsch Wikipedia
hypotension — 1. Subnormal arterial blood pressure. SYN: hypopiesis. 2. Reduced pressure or tension of any kind. [hypo + L. tensio, a stretching] arterial h. h. (1). idiopathic orthostatic … Medical dictionary
hypotension — noun The disease or disorder of abnormally low blood pressure. Ant: hypertension See Also: hypovolemia, orthostatic hypotension … Wiktionary
Hypotension — Niederdruck; Hypotonie (fachsprachlich); niedriger Blutdruck * * * Hy|po|ten|si|on 〈f. 20; Med.〉 = Hypotonie (2) * * * Hy|po|ten|si|on, die; , en [zu lat. tensio = Spannung] (Med.) … Universal-Lexikon
hypotension — n. a condition in which the arterial blood pressure is abnormally low, which is most commonly experienced when rising from a sitting or lying position (postural or orthostatic hypotension). It occurs after excessive fluid loss (e.g. through… … The new mediacal dictionary