status epilepticus

Definition

Seizure lasting greater than 20 minutes or multiple seizures from which the patient does not regain consciousness.

Epidemiology

Pathogenesis

Etiology

1. Failing to take medication
2. Sepsis
3. Meningitis/encephalitis
4. Trauma
5. Toxic/metabolic encephalopathies
6. Fever

Clinical features

Seizures may be of the convulsive (usually generalized tonic-clonic) type or non-convulsive type (e.g. abscence or partial complex). Therefore, the patient may simply appear confused or dazed. Seizures lasting longer than 20 minutes begin to produce irreversible neurologic damage or death.

Diagnosis

Laboratory

1. electrolytes, Ca++, Mg++
2. glucose
3. blood culture
4. anticonvulsant level

CSF

An LP may be necessary to rule out meningitis/encephalitis if clinical symptoms exist.

CT scan

A CT scan may be important to rule out intra-cranial hemorrhage or stroke.

Treatment

Airway

The airway must be cleared with suction and a plastic airway inserted. The patient should be placed on their side to prevent aspiration. Also be sure to loosen tight clothing and place the patient on a soft surface. The patient should not be restrained. Objects such as tongue depressors should not be placed in the mouth.

Oxygen

Oxygen by mask must be given to prevent hypoxia and avoid neurologic sequelae.

Medications

All the medications require IV access for rapid onset of action.

Benzodiazepines

Benzodiazepines will cause respiratory depression especially in children. Do not exceed the maximum dosesand avoid if barbiturates have been given.

• diazepam 0.1 mg/kg

A rule of thumb is use a maximum of 1 mg per year of age to a maximum of 10 mg. May be repeated once following phenytoin if seizures persist.

• lorazepam 0.05-0.5 mg/kg

Phenytoin

If seizure continues, may follow with phenytoin. Monitor with close ECG and BP monitoring. Cannot be given IM.

• phenytoin 10-15 mg/kg IV over 20-30 mins

May be repeated once to maximum of 30-40 mg/kg total dose.

Phenobarbital

If seizures persist, phenobarbital may be given. Phenobarbital is also an alternate choice, but respiratory depression especially following benzodiazepines is significant. Be prepared to ventilate.

• phenobarbital 10-15 mg/kg IV over 20-30 mins

This dose can be repeated to a maximum of 30-40 mg/kg total dose. If no venous access available the same dose may be given IM, but has a slower onset of action.

General anaesthetic

If seizures still persist despite the above treatment, then the patient is intubated, ventilated, paralyzed, and general anesthetic given.

Dr. Sinclair
Pediatric Neurology
Department of Pediatrics
University of Alberta
Revised: July 08, 1997