Convulsions (seizure syndrome) in children

Convulsive syndrome in children is a typical manifestation of epilepsy, spasmophilia, toxoplasmosis, encephalitis, meningitis and other diseases. Convulsions occur with metabolic disorders (hypocalcemia, hypoglycemia, acidosis), endocrinopathies, hypovolemia (vomiting, diarrhea), overheating.

Many endogenous and exogenous factors can lead to the development of seizures: intoxication, infection, trauma, CNS diseases. In newborns, seizures can be caused by asphyxia, hemolytic disease, congenital CNS defects.

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Symptoms of convulsive syndrome

Convulsive syndrome in children develops suddenly. Motor excitation occurs. The gaze becomes wandering, the head is thrown back, the jaws are closed. Characteristically, the upper limbs are bent at the wrist and elbow joints, accompanied by straightening of the lower limbs. Bradycardia develops. Respiratory arrest is possible. The color of the skin changes, up to cyanosis. Then, after a deep breath, breathing becomes noisy, and cyanosis is replaced by pallor. Convulsions can be clonic, tonic, or clonic-tonic in nature, depending on the involvement of brain structures. The younger the child, the more often generalized convulsions are observed.

How to recognize convulsive syndrome in children?

Convulsive syndrome in infants and young children is usually tonic-clonic in nature and occurs mainly in neuroinfections, toxic forms of acute respiratory viral infections and acute intestinal infections, and less often in epilepsy and spasmophilia.

Convulsions in children with elevated body temperature are probably febrile. In this case, there are no patients with convulsive attacks in the child's family, there are no indications of convulsions in the anamnesis with normal body temperature.

Febrile seizures usually develop between the ages of 6 months and 5 years. They are characterized by short duration and low frequency (1-2 times during the fever period). The body temperature during a seizure attack is over 38 °C, there are no clinical symptoms of infectious damage to the brain and its membranes. The EEG does not reveal focal and seizure activity outside of seizures, although there is evidence of perinatal encephalopathy in the child.

Febrile seizures are based on a pathological reaction of the central nervous system to infectious-toxic effects with increased seizure readiness of the brain. The latter is associated with a genetic predisposition to paroxysmal conditions, mild damage to the brain in the perinatal period, or is caused by a combination of these factors. 

The duration of a febrile seizure attack usually does not exceed 15 minutes (usually 1-2 minutes). Usually, a seizure attack occurs at the height of the fever and is generalized, characterized by a change in skin color (paleness combined with various shades of diffuse cyanosis) and breathing rhythm (it becomes hoarse, less often - shallow).

Children with neurasthenia and neurosis experience affective-respiratory seizures, the genesis of which is due to anoxia, due to short-term, spontaneously resolving apnea. These seizures develop mainly in children aged 1 to 3 years and are conversion (hysterical) attacks. They usually occur in families with overprotection. The attacks may be accompanied by loss of consciousness, but children quickly come out of this state. Body temperature during affective-respiratory seizures is normal, no signs of intoxication are observed.

Convulsions accompanying syncope are not life-threatening and do not require treatment. Muscle contractions (cramps) occur as a result of metabolic disorders, usually salt metabolism. For example, the development of repeated, short-term convulsions lasting 2-3 minutes between the 3rd and 7th days of life ("fifth-day convulsions") is explained by a decrease in zinc concentration in newborns.

In neonatal epileptic encephalopathy (Ohtahara syndrome), tonic spasms develop, occurring in series both during wakefulness and sleep.

Atonic seizures are characterized by falls due to a sudden loss of muscle tone. In Lennox-Gastaut syndrome, the muscles supporting the head suddenly lose tone, causing the child's head to fall. Lennox-Gastaut syndrome debuts between the ages of 1 and 8 years. Clinically, it is characterized by a triad of seizures: tonic axial, atypical absences, and myatonic falls. Seizures occur with high frequency, and treatment-resistant status epilepticus often develops.

West syndrome debuts in the first year of life (on average at 5-7 months). Attacks occur in the form of epileptic spasms (flexor, extensor, mixed), affecting both the axial muscles and the limbs. Short duration and high frequency of attacks per day, their grouping into series are typical. Delay in mental and motor development is noted from birth.

Emergency care for convulsive syndrome in children

If the convulsions are accompanied by severe disturbances in breathing, blood circulation and water-electrolyte balance, i.e. manifestations that directly threaten the child’s life, treatment should begin with their correction.

To stop convulsions, preference is given to drugs that cause the least respiratory depression - midazolam or diazepam (seduxen, relanium, relium), as well as sodium oxybate. A quick and reliable effect is achieved by administering hexobarbital (hexenal) or sodium thiopental. If there is no effect, nitrous oxide anesthesia with the addition of halothane (fluorothane) can be used.

In cases of severe respiratory failure, prolonged mechanical ventilation is indicated along with muscle relaxants (preferably atracurium besilate (tracrium)). In newborns and infants, if hypocalcemia or hypoglycemia is suspected, glucose and calcium gluconate should be administered, respectively.

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Treatment of seizures in children

According to most neurologists, it is not recommended to prescribe long-term anticonvulsant therapy after the first convulsive paroxysm. Single convulsive attacks that occur against the background of fever, metabolic disorders, acute infections, poisoning can be effectively stopped by treating the underlying disease. Preference is given to monotherapy.

The main treatment for febrile seizures is diazepam. It can be used intravenously (sibazon, seduxen, relanium) in a single dose of 0.2-0.5 mg / kg (in young children, 1 mg / kg), rectally and orally (clonazepam) in a dose of 0.1-0.3 mg / (kg per day) for several days after seizures or periodically for their prevention. For long-term therapy, phenobarbital (single dose 1-3 mg / kg), sodium valproate are usually prescribed. The most common oral anticonvulsants include finlepsin (10-25 mg / kg per day), antelepsin (0.1-0.3 mg / kg per day), suxilep (10-35 mg / kg per day), diphenin (2-4 mg / kg).

Antihistamines and neuroleptics enhance the effect of anticonvulsants. In case of convulsive status, accompanied by respiratory failure and the threat of cardiac arrest, it is possible to use anesthetics and muscle relaxants. In this case, children are immediately transferred to artificial ventilation.

For anticonvulsant purposes in intensive care settings, GHB is used at a dose of 75-150 mg/kg, fast-acting barbiturates (sodium thiopental, hexenal) at a dose of 5-10 mg/kg, etc.

In neonatal and infantile (afebrile) seizures, the drugs of choice are phenobarbital and diphenin (phenytoin). The initial dose of phenobarbital is 5-15 mg/kg-day), maintenance - 5-10 mg/kg-day). If phenobarbital is ineffective, diphenin is prescribed; the initial dose is 5-15 mg/(kg-day), maintenance - 2.5-4.0 mg/(kg/day). Part of the 1st dose of both drugs can be administered intravenously, the rest - orally. When using the indicated doses, treatment should be carried out in intensive care units, since respiratory arrest is possible in children.

Pediatric single dose anticonvulsants

Preparation	Dose, mg/(kg-day)
Diazepam (sibazon, relanium, seduxen)	0.2-0.5
Carbamazepine (finlepsin, tegretol)	10-25
Clobazam	0.5-1.5
Clonazepam (Antelepsin)	0.1-0.3
Ethosuximide (suxilep)	10-35
Nitrazepam	0.5-1.0
Phenobarbital	4-10
Phenytoin (diphenin)	4-15
Sodium valproate (convulex, depakine)	15-60
Lamictal (lamotrigine):
Monotherapy	2-10
In combination with valproate	1-5

Hypocalcemic seizures may occur when the total blood calcium level drops below 1.75 mmol/l or the ionized calcium level drops below 0.75 mmol/l. In the neonatal period, seizures may be early (2-3 days) and late (5-14 days). During the first year of life, the most common cause of hypocalcemic seizures in children is spasmophilia, which occurs against the background of rickets. The likelihood of seizure syndrome increases in the presence of metabolic (in rickets) or respiratory (typical for hysterical seizures) alkalosis. Clinical signs of hypocalcemia: tetanic seizures, apneic attacks due to laryngospasm, carpopedal spasm, "obstetrician's hand", positive symptoms of Chvostek, Trousseau, Lust.

Intravenous slow (over 5-10 min) administration of 10% solution of calcium chloride (0.5 ml/kg) or gluconate (1 ml/kg) is effective. Administration in the same dose can be repeated after 0.5-1 hour if clinical and/or laboratory signs of hypocalcemia persist.

In newborns, seizures can be caused not only by hypocalcemia (< 1.5 mmol/l), but also by hypomagnesemia (< 0.7 mmol/l), hypoglycemia (< 2.2 mmol/l), hyperbilirubinemia, and pyridoxine (vitamin B6) deficiency, which requires emergency laboratory screening, especially if there is no time or technical capabilities to confirm diagnostic versions.