Acute Convulsions In Children

An acute convulsion is a sudden episode of abnormal excessive neuronal activity producing involuntary motor activity, altered consciousness, or both. Most brief childhood seizures stop spontaneously. A convulsion continuing for 5 minutes or longer should be treated immediately because prolonged seizures become increasingly difficult to terminate and carry increasing risk of hypoxia, aspiration, metabolic derangement and neuronal injury.

Common causes include febrile seizures, epilepsy, meningitis, encephalitis, cerebral malaria, hypoglycaemia, electrolyte disturbances, head injury and poisoning.

Generalized convulsions typically cause loss of consciousness with tonic stiffening followed by rhythmic clonic movements.

Assess for features suggesting the underlying cause:

• Fever, meningism or rash
• Focal neurological signs
• Head trauma
• Persistent altered consciousness
• Hypoglycaemic symptoms
• Toxic exposure
• Known epilepsy or missed medication
• Recurrent focal seizures
• Signs of raised intracranial pressure

Diagnosis during an active generalized convulsion is clinical.

Immediately check:

• Bedside glucose
• Temperature
• Oxygen saturation
• Neurological state after seizure cessation

Further investigations depend on presentation and may include electrolytes, calcium, magnesium, FBC, malaria testing, renal function, toxicology, lumbar puncture and neuroimaging.

Persistent altered consciousness should not automatically be labelled postictal until hypoglycaemia, CNS infection, ongoing non convulsive status and intracranial pathology have been considered.

• Protect from injury. Do not restrain the child and do not place objects in the mouth.

• Position appropriately, maintain airway patency, suction visible secretions if required and give oxygen when clinically indicated.

• Check glucose immediately and correct hypoglycaemia.

For a seizure lasting at least 5 minutes:

• Diazepam 0.3 mg/kg IV slowly over approximately 1 minute, or 0.5 mg/kg rectally.

• Alternative: lorazepam 0.1 mg/kg IV, maximum 4 mg.

• Buccal or intranasal midazolam is appropriate when IV access is unavailable.

If seizure persists approximately 5 minutes after an adequate first dose, give a second benzodiazepine dose.

If seizures continue, move promptly to a second line anticonvulsant rather than repeatedly administering benzodiazepines.

Options include:

• Levetiracetam 40 to 60 mg/kg IV, commonly maximum 4.5 g depending on protocol.

• Phenytoin 20 mg/kg IV, maximum infusion rate 1 mg/kg/min, with ECG and blood pressure monitoring.

• Sodium valproate 20 to 40 mg/kg IV, avoiding use where significant hepatic disease or a mitochondrial disorder is suspected.

• Phenobarbital 15 to 20 mg/kg IV or IM, with close respiratory monitoring.

Persistent seizure activity despite appropriate second line therapy requires urgent anaesthetic and intensive care involvement.