Paediatrics: Status epilepticus

Status epilepticus

Status epilepticus (StE) is a prolonged seizure lasting over 30min or recur-rent seizures during which the patient does not fully regain consciousness within a 30min period. However, in practical terms, once a child has been fitting for more than 5min, the chances of the seizure lasting more than 30min are dramatically increased, and therefore the common practice is to start therapy at this point. The success of treatment depends on prompt recognition and treatment.

Symptoms

StE is classified as convulsive (C) or non-convulsive (NC). NCStE is di-agnosed with electroencephalogram (EEG), and should be considered in the comatosed.

Aetiology

The common causes of childhood StE include:

·  A regular occurrence in a child with a known/difficult epilepsy.

·  Fever.

·  Subtherapeutic anticonvulsant levels.

·  Central nervous system (CNS) infections.

·  Trauma.

·  Poisoning.

·  Metabolic abnormalities.

Note: in teenagers diagnosed with convulsive StE in the emergency depart-ment, who do not have a pre-existing disability, up to 50% will be having voluntary movements of psychological origin (‘pseudoseizures’). So con-sider whether it is definitely a genuine epileptic seizure.

Investigations

After emergency life-supporting therapies, useful diagnostic tests include:

·  Brain imaging: computerized tomography (CT), magnetic resonance imaging (MRI).

·  EEG.

·  Lumbar puncture* caution;

·  Blood: magnesium, electrolytes, calcium, glucose, and creatinine levels.

·  Arterial blood gas.

·  Toxicology: blood and urine.

·  Anticonvulsant levels in those on anticonvulsants.

·  FBC and WBC differential.

Initial treatment

At any stage, if there is respiratory depression, intubate the trachea and support breathing.

Once the seizure has stopped

Whilst the child is convulsing there is a reasonable amount of oxygen perfusing the brain. Hence, the advice to parents that home oxygen is not indicated for the treatment of StE. However, once the convulsion ends, the child may have a respiratory arrest. So this is the critical period for vigilance of ABC. Roll into the recovery position, keep the oxygen run-ning, watch the SpO₂, and other observations carefully. Do not transfer the child or perform potentially dangerous procedures, such as LP until the child has a GCS that is both improving and >9.