The medical term for fainting.
Another word for fainting – a loss of consciousness due to a fall in BLOOD PRESSURE. This may result because the cardiac output has become reduced, or because the peripheral resistance provided by the arterioles has decreased. The simple faint or vaso-vagal attack is a result of a failure to maintain an adequate venous return of blood to the heart. This is likely to occur after prolonged periods of standing, particularly if one is standing still or if the climatic conditions are hot. It can also result from an unpleasant or painful experience. Pallor, sweating and a slow pulse are characteristic. Recovery is immediate when the venous return is restored by lying ?at.
Syncope can also result when the venous return to the heart is impaired as a result of a rise in intrathoracic pressure. This may happen after prolonged vigorous coughing – the so-called COUGH SYNCOPE – or when elderly men with prostatic hypertrophy strain to empty their bladder. This is known as micturition syncope. Syncope is particularly likely to occur when the arterial blood pressure is unusually low. This may result from overtreatment of HYPERTENSION with drugs or it may be the result of diseases, such as ADDISON’S DISEASE, which are associated with low blood pressures. It is important that syncope be distinguished from EPILEPSY.
(fainting) n. loss of consciousness due to a sudden drop in blood pressure, resulting in a temporarily insufficient flow of blood to the brain. It commonly occurs in otherwise healthy people and may be caused by an emotional shock, by standing for prolonged periods, or by injury and profuse bleeding. Recovery is normally prompt and without any persisting ill-effects. See also neurocardiogenic syncope.
Temporary loss of consciousness that may be induced by a severe spasm of coughing. This is the result of the high pressure that may be induced in the chest – over 200 millimetres of mercury – by such a spasm, which prevents the return of blood to the heart. The veins in the neck begin to bulge and the blood pressure falls; this may so reduce the blood ?ow to the brain that the individual feels giddy and may then lose consciousness. (See FAINTING.)... cough syncope
(malignant vasovagal syndrome) recurrent loss of consciousness due to a drop in blood pressure mediated by *vasodilatation, *bradycardia, or a combination of the two. Attacks resemble a simple faint, but can be very disabling because they are much more frequent and severe. Treatment comprises increased fluid and salt intake together with training in postural manoeuvres that may prevent attacks. A variety of drug treatments is available, but these are commonly ineffective. Implantation of a permanent *pacemaker may be required if profound bradycardia is a feature.... neurocardiogenic syncope
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