SYNCOPE (FAINTING)

·         A common neurologic sign.

·         It is also called fainting or "passing out."

·         It usually occurs abruptly and lasts for seconds to minutes.

·         It refers to a temporary / transient loss of consciousness that is usually associated with insufficient blood flow to the brain or cerebral hypoxia.

·         It is usually occurs when blood pressure is too low (hypotension) and the heart does not pump enough blood to deliver the oxygen to the brain.

·         It can be benign or associated with an underlying medical condition.

Causes

Syncope is a symptom that can be due to several causes, ranging from benign to life threatening.

Non-life-threatening factors that also can trigger syncope, such as-

·         Overheating,

·         Dehydration,

·         Heavy sweating,

·         Exhaustion or the pooling of blood in the legs due to sudden changes in body position.

Neurally Mediated Syncope (NMS)

·         NMS is the most common form of fainting.

·         It also called reflex, neurocardiogenic, vasovagal (VVS) or vasodepressor syncope.

·         It is benign and rarely requires medical treatment.

·         NMS is more common in children and young adults, but it can occur at any age.

·         It happens when the part of the nervous system that regulates blood pressure and heart rate malfunctions in response to a trigger, such as emotional stress or pain.

·         NMS typically happens while standing and often preceded by a sensation of warmth, nausea, light-headedness, tunnel vision or visual "grayout." Placing the person in a reclining position restores blood flow and consciousness, and ends the seizure.

·         Situational syncope, - a type of NMS, is related to certain physical functions, such as violent coughing (especially in men), laughing or swallowing.

·         Other Causes - Drugs.

o   Quinidine may cause syncope — and possibly sudden death — associated with ventricular fibrillation.

o   Prazosin may cause severe orthostatic hypotension and syncope, usually after the first dose.

o   Occasionally, griseofulvin, levodopa, and indomethacin can produce syncope.

Cardiac Syncope

·         Cardiac or cardiovascular syncope is caused by various heart conditions, such as bradycardia, tachycardia or certain types of hypotension.

·         It can increase the risk of sudden cardiac death.

·         Several serious heart conditions can also cause syncope, such as -Condition that produce sever bradycardia, tachycardia or blood flow obstruction

o   Aortic arch syndrome.

o   Aortic stenosis.

o   Cardiac arrhythmias.

o   Hypoxemia.

o   Orthostatic hypotension

o   Transient ischemic attack (TIA)

o   Heart failure

·         Cardiac syncope is a higher risk in:

o   People older than age 60;

o   Men;

o   Presence of known heart disease;

o   Brief palpitations or sudden loss of consciousness;

o   Fainting during exertion;

o   Fainting while supine;

o   An abnormal cardiac exam;

o   Family history of inheritable conditions.

Clinical Mainefestation

Signs and symptoms that may happen before a fainting episodes are-

·         Feeling of heaviness in the legs

·         Blurred or "tunnel" vision

·         Confusion

·         Feeling warm or hot

·         Light-headedness, dizziness, a floating feeling

·         Dizziness

·         Nausea and vomiting

·         Yawning.

·         Sweating

Signs and symptoms when a person faints are-

·         Fall over or slump

·         Appear unusually pale

·         Experience a drop in blood pressure and a weak pulse

Assessment and treatment

·         People who experience the warning signs of fainting of dizziness, nausea and sweaty palms should sit or lie down.

·         Anyone with syncope should receive an initial evaluation, including detailed physical and history examinations and measurement of blood pressure and heart rate.

·         ECG – if abnormal heart rhythms found other tests, such as exercise stress test, Holter monitor and an echocardiogram. It may needed to rule out other cardiac causes.

·         If the initial evaluation is unclear. It may be useful for patients to undergo a tilt test. The blood pressure and heart rate will be measured while lying on a board and with the board tilted up.

o   People with NMS usually will faint during the tilt, due to the rapid drop in blood pressure and heart rate. When people are placed on their back again, blood flow and consciousness are restored.

·         For people who are dehydrated, it may be beneficial to increase their salt and fluid intake to prevent syncope.

·         If syncope is associated with an underlying medical condition than treat that problem.