Fainting: causes, symptoms, consequence of loss of consciousness

Fainting is a condition that, for sure, has never happened in everyone’s life, but it is familiar as such. Fainting is called an attack of sudden, but short-term loss of consciousness, the conditionality of which is a temporary violation of cerebral blood flow. In addition to cases of syncope of a neurogenic or other nature, loss of consciousness can occur as a manifestation of various conditions and a symptom of various diseases.

Causes of fainting and other types of loss of consciousness

Spontaneous loss of consciousness is divided into short- and long-term (persistent), neurogenic and somatogenic origin.

Short-term loss of consciousness usually does not pose a danger to life, lasts from a few seconds to several minutes, has no serious consequences and in most cases does not require medical intervention.

Accompanying the following conditions of the body:

  • fainting;
  • epilepsy;
  • hypoglycemia (temporary lowering of blood glucose level);
  • disorders of cerebral circulation (eg, fatigue or lack of oxygen);
  • abrupt changes in blood pressure;
  • brain concussion.

A persistent loss of consciousness happens with more serious consequences for the body. Even with timely medical care and resuscitation, such conditions pose a danger to human health and life. They include:

  • extensive cerebral hemorrhage, stroke;
  • stop or severe heart rhythm disturbances;
  • rupture of the aortic aneurysm (subarachnoid hemorrhage);
  • different types of shock;
  • severe craniocerebral injury;
  • acute poisoning of the body;
  • damage to vital organs and internal bleeding, heavy blood loss;
  • various kinds of asphyxia, conditions that develop as a result of oxygen starvation;
  • diabetic coma.

Loss of consciousness of a neurogenic origin is observed in the picture of primary peripheral autonomic failure. It is also called progressive vegetative insufficiency, which has a chronic course and is represented by such diseases as idiopathic orthostatic hypotension, stri-nigral degeneration, Shay-Drageer syndrome (variants of multiple system atrophy).

Loss of consciousness of somatogenic origin is observed in the picture of secondary peripheral insufficiency. It has an acute course and develops against a background of somatic diseases (amyloidosis, diabetes mellitus, alcoholism, chronic renal failure, porphyria, bronchial carcinoma, leprosy and other diseases). Vertigo in the picture of peripheral vegetative deficiency is always accompanied by other characteristic manifestations: anhidrosis, a fixed heart rhythm and so on.

In general, a variety of circumstances can cause loss of consciousness, for example:

  • severe hypothermia or overheating, consequently, freezing or heat stroke;
  • lack of oxygen;
  • dehydration of the body;
  • severe pain and traumatic shock;
  • emotional shock or nervous tension.

Causes of fainting may lie in insufficient oxygen in the blood for choking, poisoning, metabolic disorders, for example, hypoglycemia or uremia, diabetes mellitus. Loss of consciousness in its basis can also have a direct effect, such as head trauma, hemorrhage of a different nature (mainly to the brain), poisoning (eg, alcohol or fungi), as well as indirect effects (eg, internal and extensive external bleeding, heart disease and inhibition of the brain center responsible for blood circulation).

Clinical manifestations of loss of consciousness

Usually it is syncope that is the symptom of a more serious illness, indicating the need to consult a medical specialist, make up or correct a treatment regimen. In certain cases, fainting pass without a trace. Nevertheless, loss of consciousness is accompanied by a wide range of symptoms – from exclusively fainting to a complex of symptoms and organic disorders during coma or clinical death.


As it was said earlier, fainting is a sudden and short-term loss of consciousness, which arises from temporary damage to the cerebral blood flow. Symptoms of fainting are usually a feeling of faintness and nausea, clouded consciousness, flickering in the eyes, ringing in the ears. The patient develops weakness, there is a yawn, legs are weak, the person pales, and at times the sweat appears. In the shortest possible time, there is a loss of consciousness – the pulse becomes faster or faster, the muscles slow, the muscles become weaker, the neurological reflexes disappear or weaken, the pressure decreases, the heart sounds fade, the skin becomes pale and gray, the pupils expand, and their reaction to light decreases. At the peak of syncope or in case of excessive duration it is likely the development of seizures and involuntary urination.

It is necessary to distinguish between faints of epileptic and non-epileptic nature. Syncope of non-epileptic nature develops under the following pathological conditions:

  • reduction of cardiac output – cardiac rhythm is disturbed, stenosis of the aorta or pulmonary arteries, attack of angina or infarction;
  • violation of nervous regulation of blood vessels – for example, with a rapid reception of the vertical position from the horizontal;
  • lowering the oxygen content in the blood – anemia, asphyxia, hypoxia.

Epileptic seizure

It develops in persons with epilepsy. Its occurrence depends on a combination of intracerebral factors – activity of the convulsive focus and general convulsive activity. Epileptic seizure-provoking factors can be various states of the body (menstruation, sleep phase, etc.) and external influences (for example, flickering light). Difficulties in determining the seizure may be due to the fact that, in certain cases, epipristide passes without convulsions, there are no characteristic symptoms. Diagnostic information provides a blood test for the content of creatine phosphokinase and electroencephalography (EEG).

The epileptic attack begins suddenly with tonic muscle contractions, taking about a minute and passing into a phase with sharp jerking of the entire body. Often the seizure begins with a cry. In the prevailing number of cases, saliva with blood impurities is released from the mouth. Epileptic dizziness and fainting are less common and are often combined with seizures due to cardiovascular disorders. The correct diagnosis can be made with their recurrent character without signs of circulatory disturbance.


Hypoglycemia is a pathology that develops when the concentration of glucose in the blood decreases. The causes of the fall in sugar levels can be dehydration, irrational nutrition, excessive physical activity, ailing body condition, alcohol abuse, hormone deficiency and other factors.

The manifestations of hypoglycemia are as follows:

  • excitement and increased aggressiveness, anxiety, anxiety, fear;
  • excessive sweating;
  • arrhythmia and tachycardia;
  • tremor and muscle hypertonia;
  • dilated pupil;
  • visual impairment;
  • pallor of the skin;
  • increased blood pressure;
  • disorientation;
  • headache, dizziness;
  • violation of coordination of movements;
  • focal neurological disorders
  • respiratory and circulatory disorders (central genesis).

Hypoglycemia with rapid development of it can contribute to neurogenic syncope in persons predisposed to it or lead to a co-morbid and coma.

Craniocerebral injury

Craniocerebral trauma – damage to the bones of the skull and / or soft tissues (brain tissue, vessels, nerves, meninges). Depending on the complexity of the damage, several types of CCI are distinguished:

  • concussion of the brain – trauma, not accompanied by persistent disruption in the brain; Symptoms that occur in the first time after the injury, or pass during the next few days, or mean more serious damage to the brain; the main criteria for the severity of the concussion are the duration (from a few seconds to hours) and the subsequent depth of loss of consciousness and amnesia;
  • a bruise of the brain – distinguish bruises of light, medium and heavy degree;
  • compression of the brain – possibly through a hematoma, foreign body, air, foci of injury;
  • diffuse axonal injury;
  • subarachnoid hemorrhage.

Symptoms of CCI is a disorder or loss of consciousness (sopor, coma), damage to the cranial nerves, hemorrhages in the brain.

Shock condition

Shock is a pathological state of the organism, developed by the action of a superstrong stimulus, which causes disturbances in vital functions. The causes of shock and loss of consciousness on its background are in severe conditions of the body, which are accompanied by:

  • severe pain reaction;
  • large blood loss;
  • extensive burns;
  • combination of these factors.
  • The shock state is manifested by a number of symptoms:
  • instantaneous suppression of the body’s functions after a brief excitation;
  • inhibition and indifference;
  • the skin is pale and cold;
  • the appearance of sweating, cyanosis or greyness of the skin;
  • weakening of the pulse and acceleration of its frequency;
  • breathing is frequent, but superficial;
  • dilated pupils, in the subsequent loss of vision;
  • possibly, vomiting.

First aid for unconsciousness

Loss of consciousness is such a condition that can pass without a trace to the body, can mean a dangerous symptom of the developing disease, and may already at this particular moment represent a danger to the life of the victim. Therefore, in spite of the need to seek professional help in a timely manner, it is necessary to know the measures of the first pre-medical care for a person who has lost consciousness.

With fainting

The main danger of syncope is that all muscles are relaxed, including the tongue, the sinking of which can block the airways. Before the arrival of the ambulance team, it is necessary to provide the victim with a recovery position – on his side. Since at the stage of first aid it is not always possible to determine the cause of syncope, for example, to differentially diagnose syncope from coma, it is mandatory to seek professional help.

With an epileptic seizure

The goal of first aid for an epileptic seizure is to prevent harm to the health of the epileptic. The onset of an attack is frequent, but not always accompanied by loss of consciousness and a person’s falling to the floor, which must be prevented if possible in order to avoid contusions and fractures. Then it is necessary to hold the person’s head, promote the outflow of saliva through the corner of the mouth, so that it does not get into the respiratory tract. If the jaws of the victim are tightly closed, do not try to open them. After the cramping and relaxation of the body, it is necessary to put the victim in a restorative position – on his side, this is necessary to prevent the rooting of the tongue. Usually 10-15 minutes after the attack, a person completely comes to his normal state and first aid is no longer needed.

With hypoglycemia

Loss of consciousness in hypoglycemia usually does not develop spontaneously, this is preceded by the gradually deteriorating state of health of the victim. Patients who are already in a state of hypoglycemia are already unconscious, never give liquids or other food, because this can lead to undesirable consequences, for example, asphyxia. As a first aid in such situations, 1 mg of glucagon should be administered intramuscularly, it indirectly causes an increase in the glucose level in the blood. In hospital conditions, intravenous administration of 40% glucose is more accessible than glucagon, and as a result leads to a rapid return of consciousness.

With traumatic brain injury

In the presence of an episode with loss of consciousness, the patient regardless of his current condition needs to be transported to a hospital. This is due to the high potential risk of developing severe life-threatening complications. After admission to the hospital, the patient is clinically examined, is collected at the opportunity of anamnesis, and the nature of the trauma is specified for him or the accompanying persons. Then a complex of diagnostic measures aimed at checking the integrity of the skeletal skeleton skeleton and the presence of intracranial hematomas and other brain tissue damage is performed.

In shock

First aid is to provide the patient with peace. If his condition is accompanied by a fracture of the limb, immobilize it, if wounded – stop bleeding by applying a bandage or a tourniquet. To improve the flow of blood to the brain and heart, lift the victim’s legs slightly above the level of the head, warm it – cover with outer clothing or wrap up with a blanket. If consciousness is preserved and there is no danger of vomiting, give the patient anesthetics and drink. Loss of consciousness is an unfavorable symptom, which means an urgent need to seek professional help. Urgent hospitalization is necessary.

The above listed cases are not exhaustive states of fainting, and then it is necessary to adequately respond to the condition of a person and certainly seek professional help if a syncope touched a pregnant woman, an elderly person or a person with visible manifestations of other diseases.

Leave a Reply

Your email address will not be published. Required fields are marked *