Fainting in children

Syncope in children (Greek synkope - loss of sound) is a sudden development of a sharp deterioration in the state of health, accompanied by vascular dystonia, short-term impairment of consciousness, a decrease in muscle tone and a fall.

Most fainting is observed in school-age children, which reflects the imperfection of vegetative regulation of vascular tone during the pubertal period.

[1], [2]

Causes of fainting in children

The onset of syncope in children is associated with an acute disorder of brain metabolism due to its deep hypoxia or hypoglycemia. Usually, reflex neurogenic spasm of cerebral vessels and concomitant parasympathetic influence (n. Vagus) on the heart and blood vessels are noted, which is accompanied by a sharp decrease in the tone of the peripheral vessels, bradycardia.

EN Ostapenko (1995) identifies the following most common syncope in children due to a primary disruption of cardiovascular regulation:

• vasodepressive syncope in children occurs most often (usually in connection with a stressful situation, for example, at the time of medical manipulation - injection);
• orthostatic hypotension - functional (due to a sedentary lifestyle) and organic (against diabetes mellitus, amyloidosis, CNS tumors, etc.); is caused by a lack of vasopressor mechanisms;
• reflex syncope in children develops in response to manipulations on the reflex zones (throat, larynx, bronchi, carotid sinus, etc.) and is associated with irritation of the vagus nerve. Carotid sinus syndrome can occur with mechanical stimulation (palpation) in the zone of projection of carotid artery bifurcation and be cardioinhibitory and vasodepressor in response form;
• situational syncope in children occurs with a fit of coughing, straining with defecation or difficulty urinating, lifting the heaviness due to a sharp increase in intrathoracic pressure, which hinders the outflow of blood from the brain;
• Hyperventilation syndrome develops most often in hysteria; the syncope in children causes secondary respiratory alkalosis, hypocapnia, cerebral vasospasm and its ischemia.

[3], [4], [5], [6]

How does the syncope manifest in children?

In the clinical picture of syncope in children, three successively changing stages can be observed: the appearance of precursors (pre-fainting condition), impaired consciousness and the recovery period.

First, there are subjective sensations in the form of discomfort, increasing weakness, dizziness, darkening in the eyes (gray veil), noise in the ears, spastic abdominal pain, increased sweating, decreased muscle tone. The duration of this stage does not exceed 1 min (usually several seconds). In the case of timely measures (lying down, accessing fresh air), it is possible to prevent a loss of consciousness.

Unconsciousness during fainting lasts several minutes, rarely - more. During this period, the paleness of the skin, the dilatation of the pupils without reaction to light, bradycardia, lowering of the blood pressure, respiratory depression (it becomes superficial, rare), oppression of reflexes (including corneal), relaxation of all muscles.

The diagnosis of syncope is based on a typical clinical picture. It occurs suddenly, usually with the vertical position of the child, in a certain situation (stuffiness, crowdedness, fuss, stress).

In the genesis of sudden confusion of consciousness with falling, there may be other causes: complete AV blockade of the heart (Morgagni-Adams-Stokes syndrome), epilepsy (small forms), embolization of cerebral vessels, cerebral circulation, severe anemia, etc. Therefore, careful differential diagnosis both in the course of assisting the child during a syncope, and afterwards to eliminate organic pathology.

What if the child fainted?

Help in fainting a child is aimed at improving the blood supply to the brain. In no case can you support a sudden unconscious child in a vertical or sitting position - it should be laid, slightly raising one's legs. If a child faints, it usually does not hurt. The patient needs to unbutton the gate, provide access to fresh air, bring to the nose cotton wool soaked with ammonia (10% aqueous ammonia solution), sprinkle his face with cold water, lightly pat his cheeks. Fainting in children can also be treated with subcutaneous injections of cordiamine, caffeine (25%) at a dose of 0.1 ml for each year of life.