Fainting - Causes, symptoms and treatment. MF.
Apr 18, 2018
Symptoms similar to Fainting:
• Failure of
memory • Loss of consciousness
Syncope( syncope) is a short-term loss of consciousness and a fall in the background of a sudden decrease in metabolism in the brain. Most often this decline occurs as a result of a short-term disturbance of cerebral blood flow and, consequently, a lack of oxygen to the brain. This leads to dizziness or loss of consciousness. Temporary impairment of blood supply to the brain can be caused by heart disease or other causes that do not directly touch the heart.
Syncope is always accompanied by with a pre-fog condition - a person experiences a feeling of faintness, circles before the eyes, palpitations, thudding in the temples, sweating, hot flashes, nausea, a feeling of approaching falling. If you do not sit on time, there is a loss of consciousness and a fall. The loss of consciousness is short-lived( a few seconds), and the person quickly wakes up, being in a horizontal position. Rarely there are short-term twitching of the extremities, urinary leakage and other symptoms.
Causes leading to a decrease in cerebral blood flow and syncope:
1. Disturbance of the autonomic nervous system, resulting in improper regulation of vasoconstriction - the cause of neurogenic syncope( account for more than 50% of all syncope)
2. Heart pathology - the cause of cardiogenic syncope( 25% of all syncope)
3. Vascular disorders( significant atherosclerotic deposits in the vessels of the head and neck, transient ischemic attacks, strokes)
4. Sudden increase in intracranial pressure( op(hypoxia, anemia, hypoglycemia, renal and hepatic insufficiency)
6. Decrease in the volume of circulating blood( bleeding, excessive urination, diarrhea)
7. Poisoning( blood loss, excessive urination, diarrhea).carbon monoxide, alcohol, etc.)
8. Mental disturbances( hyperventilation syndrome, hysterical neurosis)
9. And also distinguish other forms of loss of consciousness - as a result of epilepsy, craniocerebral trauma, infections, etc.
Consider onand more frequent types of syncope: neurogenic, cardiogenic, hyperventilation.
1. Vasodressor - occurs in young people in certain situations - with pain, fear, emotional stress, the form of blood, stuffiness, prolonged standing;vasodepressor syncope is the overwhelming majority of cases of syncope of all types of
2. Orthostatic - occurs with a sharp rise, taking certain medications( antihypertensive, antidepressant, levodopa)
3. Fainting with increased sensitivity of the carotid sinus - occurs in elderly men with atherosclerosis and hypertension when worntight collars
4. Fainting with increased intrathoracic pressure - occurs with nocturnal urination in elderly men, with cough, defecation
CarDiogenetic syncope of occurs in cases of heart rhythm disorders, blockade of conduction, myocardial infarction.
Hyperventilation syncope occurs in an attack of anxiety, fear, panic attack( vegetative crisis) as a result of unconscious acceleration and deepening of breathing.
With bradycardia ( when the heart rate is below 60 beats per minute), there may be short-term loss of consciousness( seconds) - "walked-went - came to the senses lying on the floor."It is important to note that the frequency difference of cuts should be sharp and fast, up to 20-30 beats per minute. Attack bradycardia can be preceded by a feeling of "hot flush in the head."Such fainting states are caused by a sharp decrease in blood supply to the brain and are characteristic of various types of arrhythmias.
Diseases that can cause syncope
• Aortic stenosis
• Low blood pressure
• Parkinson's disease
• Pulmonary hypertension
Possible causes of syncope
- Dysfunction of the autonomic nervous system
- Heart pathology
- Sudden increase in intracranial pressure( tumor, hydrocephalus, hemorrhage)
- Poisoning( by carbon monoxide, alcohol, etc.)
- Mental disorders( hyperventilation syndrome, hysterical neurosis) Epilepsy
- Craniocerebral injury
Causesloss of consciousness
Syncope is most often caused by causes that do not directly touch the heart:
• Postural( orthostatic) hypotension: lowering blood pressure due to treasoniem posture to an upright position after lying or sitting;
• Nerve diseases on the legs in the elderly( especially with diabetes or Parkinson's disease)
• High altitude of
• Fainting in certain situations( situational syncope), such as:
Coughing that causes an involuntary reflex of the nervous system( vasovagal reaction), which slows heartbeat and dilates the blood vessels in the legs, a person feels nausea, sweating, weakness shortly before fainting.
Causes related to the heart: heart disease that can cause fainting or unconsciousness:
• Pathological heart rhythm( heart beating too fast or too slowly).
• Heart valve anomalies( aortic stenosis or stenosis of the pulmonary valve).
• High blood pressure in the artery supplying the lungs( pulmonary arterial hypertension).
• Aortic dissection.
• Widespread heart disease( cardiomyopathy).
Medications can cause loss of consciousness by changing blood pressure or by affecting the heart.
Syncope in children and adolescents vasovagal
Vasovagal syncope in children and adolescents usually develops on the background of stress, fatigue or hunger, therefore it is recommended to avoid these conditions.
Vasovagal syncope accounts for about 50% of all fainting. They are often found in healthy people and often occur repeatedly.
Vasovagal syncope is provoked by
- agitation( in this case they develop more often in a stuffy, crowded room),
- with fear( for example, at a dentist's reception),
- trauma or
Quite often fainting develops for no apparent reason.
Classic vasovagal syncope is accompanied by arterial hypotension, bradycardia, nausea, pallor and profuse sweating.
The mechanism of fainting is as follows. In response to a decrease in venous return and a decrease in the shock volume, the sympathetic tone is reflexively increased. In people predisposed to such fainting, such an increase in sympathetic tone is excessive, and this leads to a sharp increase in contractility of the heart. From mechanoreceptors of the ventricles along the afferent fibers of group C of the vagus nerves, intensive impulses enter the medulla oblongata, and this is accompanied by a decrease in the sympathetic nerves and an increase in the parasympathetic tone. As a result, excessive peripheral vasodilation and relative bradycardia develop, which leads to a drop in blood pressure and fainting. Consciousness is quickly restored in a prone position with raised legs.
A test on an orthostatic table( prolonged exposure at an angle of 60-80 *) can provoke a faint in such patients. Isoprenaline in low doses increases the sensitivity of this sample, but in high doses can lead to false positive results.
Vasovagal syncope sometimes occurs in response to severe pain, especially from the internal organs. Occasionally, he accompanies a migraine attack.
Syncope during urination occurs more often in older men during and after urination, usually after sleep. Perhaps it is a kind of vasovagal syncope. Reduction of pressure in the bladder causes vasodilation and bradycardia due to increased parasympathetic tone.
To which doctors to contact if there are Fainting:
- Ambulance therapist