Status Epilepticus

Defined as continuous seizures (_15–30 min) or repetitive, discrete seizures with

impaired consciousness in the interictal period. May occur with all kinds of seizures: grand mal (tonic-clonic) status, myoclonic status, petit mal status, and temporal lobe (complex partial) status. Generalized, tonic-clonic seizures are most

common and are usually clinically obvious early in the course. After 30–45 min,

the signs may become increasingly subtle and include only mild clonic movements

of the fingers or fine, rapid movements of the eyes. In some situations, EEG may

be the only method of diagnosis. Generalized status is life-threatening when accompanied by hyperpyrexia, acidosis (from prolonged muscle activity), respiratory or cardiovascular compromise. Irreversible neuronal injury may occur from persistent seizures, even when pt is paralyzed from neuromuscular blockade.

Etiology

Principal causes of tonic-clonic status are antiepileptic drug withdrawal or noncompliance, metabolic disturbances, alcohol or drug related, CNS infections,

CNS tumors, refractory epilepsy, cerebrovascular disease, and head trauma.

TREATMENT

Generalized tonic-clonic status epilepticus is a medical emergency. Pts must

be evaluated promptly and appropriate therapy instituted without delay (Fig.

22-1). In parallel, it is essential to determine the cause of the seizures to

prevent recurrence and treat any underlying abnormalities.

1. Assess carefully for evidence of respiratory or cardiovascular insufficiency.

Withcareful monitoring and standard airway protection, pts usually

do not require intubation (if intubation is necessary, use short-acting paralytics).

Treat hyperthermia. Establish IV and administer 50 mL 50% dextrose

in water, 100 mg thiamine, and 0.4 mg naloxone.

2. Perform a brief medical and neurologic examination; send samples

for laboratory studies aimed at identifying metabolic abnormalities (CBC with

differential, serum electrolytes including calcium, glucose, liver and renal

function tests, toxicology if indicated).

3. Administer lorazepam, 0.1 mg/kg (4–8 mg) at 2 mg/min.

4. Immediately after lorazepam, administer phenytoin, 20 mg/kg (1000–

1500 mg) IV slowly over 20 min (50 mg/min) or fosphenytoin, 20 mg/kg

(150 mg/min). Monitor bp, ECG, and, if possible, EEG during infusion.

Phenytoin can cause precipitous fall in bp if given too quickly, especially in

elderly pts. (Do not administer phenytoin with 5% dextrose in water—

phenytoin precipitates at low pH. This is not a problem with fosphenytoin.)

If seizures are not controlled, a repeat bolus of phenytoin (5–10 mg/kg) or

fosphenytoin (5–10 mg/kg) may be given.

5. If seizures persist, administer phenobarbital 20 mg/kg (1000–1500 mg)

slowly over 30 min. Endotracheal intubation will often be required by this stage.

If seizures continue, give additional dose of phenobarbital (5–10 mg/kg).

6. If seizures remain refractory after 60–90 min, consider placing pt in

midazolam, propofol, or pentobarbital coma. Consultation witha neurologist

and anesthesiologist is advised.

Prognosis

The mortality rate is 20% in tonic-clonic status, and the incidence of permanent

neurologic sequelae is 10–30%.