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Relating to syncope.
Synonym(s): syncopic
Farlex Partner Medical Dictionary © Farlex 2012


Relating to syncope.
Synonym(s): syncopic.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


(sing'ko-pe, sin') [Gr. synkope, fainting]
Transient (and usually sudden) loss of consciousness, accompanied by an inability to maintain an upright posture. Syncope is a common occurrence, accounting for about 1% to 3% of all hospital admissions in the U.S.syncopal (-pal), adjective


The most frequent causes of syncope are vasovagal (the common fainting spell), cardiogenic (esp. arrhythmogenic, valvular, or ischemic), orthostatic (such as due to dehydration or hemorrhage), and neurogenic, e.g., due to seizures. Many medications (such as sedatives, tranquilizers, excessive doses of insulin), food allergies, hypoglycemia, hyperventilation, massive pulmonary embolism, aortic dissection, atrial myxoma, carotid sinus hypersensitivity, coughing, urination, and psychiatric disease can also result in loss of consciousness.


The patient typically complains of having suffered a sudden and unexpected fall to the ground, with loss of awareness, and then rapid recovery of orientation. Lacerations, abrasions, or other injuries occasionally result from the fall.


The history may contain useful clues. For example, if the patient stood up just before losing consciousness, an orthostatic cause is likely; if a patient is confused or disoriented for a long time after losing consciousness, seizures are probable; if a young patient passes out while at a wedding or other stressful event, vasovagal syncope is likely. The diabetic patient who becomes agitated and sweaty before passing out should be rapidly assessed and treated for low blood sugar.

The examination of the patient may reveal the cause; e.g., a loud aortic murmur may point to valvular heart disease, and a pale patient with orthostatic vital signs may be dehydrated or bleeding. Electrocardiographic monitoring after the event may reveal arrhythmias or evidence of ischemia. Depending on clinical circumstances, further evaluation may include carotid sinus massage, 24-hour ambulatory monitoring, month-long event monitoring, implantable loop monitoring, tilt-table testing, echocardiography, or psychiatric evaluation. In most cases, despite thorough evaluation, a precise diagnosis is not determined.

Patient care

Any person with sudden loss of consciousness should be placed in a supine position, preferably with the head low to facilitate blood flow to the brain. At the same time, a clear airway should be ensured. Clothing must be loosened, esp. if the collar is tight.

Fainting (one form of syncope) is usually of short duration and is counteracted by placing the person supine. If recovery from fainting is not prompt and complete, a prompt assessment of airway, breathing, circulation, and cardiac rhythm is needed; assistance should be obtained and the person transported to a hospital. A person who refuses hospital evaluation after recovering from a fainting episode should be encouraged to be examined by a physician as soon as possible.

cardiac syncope

Syncope of cardiac origin as in Stokes-Adams syndrome, aortic stenosis, tachycardia, bradycardia, or myocardial infarction.

carotid sinus syncope

Syncope resulting from pressure on, or hypersensitivity of, the carotid sinus. It may result from turning the head to one side or from wearing too tight a collar.

convulsive syncope

Syncope followed by a seizure. It may be caused by any condition (such as cardiac arrhythmia) that results in inadequate blood flow to the brain.

defecation syncope

Syncope during or immediately after a bowel movement.

deglutition syncope

Syncope triggered by swallowing. It is an abnormal reflex in which stimulation of the esophagus elicits vagal motor impulses that cause bradycardia, peripheral vasodilation, and hypotension.

hysterical syncope

Syncope resulting from a conversion reaction.

laryngeal syncope

Brief syncope following coughing and tickling in the throat.

local syncope

Numbness of a part with sudden blanching, as of the fingers. It is a symptom of Raynaud disease or of local asphyxia.

micturition syncope

Syncope during urination. It usually occurs in men who get up at night to urinate and is mediated by an increase in vagal tone.

neurocardiogenic syncope

Vasodepressor syncope.

prostatic syncope

Fainting during examination of the prostate. It is a rare occurrence that usually can be avoided if the patient is examined in the lateral recumbent position.

shallow water syncope

Syncope during diving that occurs when a diver hyperventilates and then holds his or her breath while swimming underwater for an extended period before resurfacing. The loss of consciousness may result in drowning or near-drowning.

situational syncope

Syncope that occurs only in certain distinct clinical circumstances, e.g., after urinating, coughing, or having a bowel movement). It is sometimes associated with inadequate return of blood to the right side of the heart, Valsalva maneuver, or increased parasympathetic tone.

tussive syncope

Syncope following a paroxysm of coughing.
Synonym: laryngeal vertigo

vasodepressor syncope

The common fainting spell.


The patient, who may have just experienced a stressful or emotionally upsetting event, reports a feeling of wooziness, nausea, and weakness, followed often by a feeling that darkness is closing in on him. A ringing in the ears may follow, along with inability to maintain an erect posture. Witnesses may report profuse sweating or a loss of color in the face. During the event, an unusually slow pulse may be present. Several convulsive movements of the body may be noted if blood flow to the brain is inadequate but the loss of consciousness is not accompanied by other signs of seizures, e.g., tongue biting, incontinence, or a prolonged postictal period of confusion.

Patient care

Placing the patient in a sitting position with the head lowered between the legs or in a horizontal or Trendelenburg position restores blood flow to the brain and promptly aborts the attack. A brief examination should be performed to make sure the affected person can move all extremities and facial muscles and can speak clearly and understand speech. The carotid arteries should be checked for bruits, and the heart for evidence of arrhythmia or heart murmurs. Blood pressure, pulse, and oxygenation, as well as cardiac rhythm, should be monitored. Fluids should be administered by mouth if nausea has resolved, or by vein if the patient cannot take liquids orally and has an intravenous access in place. An electrocardiogram should be obtained or cardiac monitoring ordered if the patient has a history of cardiac disease, is elderly, or has multiple risk factors for cardiac disease or dysrhythmias. A complete blood count, serum electrolytes, blood urea nitrogen, creatinine, and glucose should be checked. Before the patient is allowed to get up again, vital signs should be checked; if they are normal, the patient should be assisted first to a sitting position and then to a standing position before walking independently. Patients who faint may need specialized follow-up examination, e.g., with a cardiologist, internist, or neurologist.

Synonym: vasovagal syncope; neurocardiogenic syncope

vasovagal syncope

Vasodepressor syncope.
Medical Dictionary, © 2009 Farlex and Partners

Patient discussion about syncopal

Q. i am 12 and my hair is falling out what do i do? there is like a hair ball in my tub

A. First of all you are going through puberty and the hormonal levels in your body are changing, this could cause accelerated hair loss that will go away. However, if you feel like you are having severe hair loss you should go and get blood tests for the evaluation of several vitamin defficiencies (B12, Folic acid and Iron), that can be the reason. Soemtimes a lack in our nutrition can be the reason for losing hair.

Q. I found out 1week ago i was 6wks pregnant and lastnight i passed a 1/2dollar size clear ball did i miscarrie? the ball was clear,soft and jellie like and it came w/a lot of blood but i didnt see no signs of a baby or anything like that

A. Possibly, but not essentially. In this age the embryo is quite small (several millimeters), so you may easily mistaken it. My best advice is to consult a doctor (e.g. gynecologist) so an US or other test can be done to accurately diagnose a miscarriage.

Take care,

More discussions about syncopal
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References in periodicals archive ?
While in the ED, the patient had a witnessed syncopal event.
However, in light of recent use of ibrutinib in our patient, a medication that has been linked to cardiac side effects as well as with absence of any history of prior syncopal or presyncopal symptoms, the hypothesis that ibrutinib use resulted in profound depression of the sinus node or aggravated preexisting subclinical sinus node dysfunction has to be entertained.
73-year-old male came to the ED with a syncopal episode when he got up from the chair after eating lunch in a restaurant.
Novel cardiovascular biomarkers in unexplained syncopal attacks: the SYSTEMA cohort.
There was a history of one episode of syncopal attack, exertional breathlessness (NYHA grade II), and easy fatiguability.
Four cardinal clinical features characterise the syncopal episode: (i) it is transient; (ii) it has a rapid onset; (iii) it has a short duration (lasting seconds to several minutes); and (iv) there is spontaneous complete recovery requiring no resuscitative efforts.
M reported a syncopal attack and continued "dizziness." His PCP prescribed fludrocortisone, 0.1 mg/d, later to be dosed 0.2 mg/d, and symptoms improved.
who is a 48-year-old woman who experienced frequent syncopal episodes while working a 12-hour shift as a registered nurse.
Approximately one year later, she had a syncopal episode with a repeat unremarkable cardiac workup including electrocardiogram, transthoracic echocardiogram, and holter monitor, and the event was attributed to vasovagal syncope.
Alpha-blockers are effective, but are associated with orthostasis and syncopal events.
Surgeon Clayton had found no external marks or injuries on the victim, who had died from syncopal asphyxia - a heart attack.
A woman, 78 years of age, who had a 4-day history of fevers, chills, fatigue, and myalgias sought medical treatment after a syncopal episode.