Status epilepticus

G41.0-2/G41.8-9

DESCRIPTION

Status epilepticus is defined as either:

  1. two or more sequential seizures, lasting more than 5 minutes without full recovery of consciousness between seizures or;
  2. continuous seizure activity for longer than 5 minutes.

GENERAL MEASURES

Start treatment immediately. Do not wait for results of special investigations.

Place the patient in a lateral (recovery) position.

Stabilise the patient (i.e. secure airway and check breathing and circulation).

Time seizure from its onset.

Assess oxygenation and give oxygen via nasal cannula/face mask if required.

Check serum glucose, and treat if hypoglycaemic.

Secure intravenous access.

Check electrolytes (e.g. sodium, calcium, urea).

Consider poisoning, e.g. isoniazid, theophylline, tricyclic antidepressants and cocaine poisonings.

MEDICINE TREATMENT

Seizures should be stopped promptly, as prolonged seizures can cause permanent brain damage. Aim for definitive control within 60 minutes of onset.

INITIAL TREATMENT

Benzodiazepine:

  • Lorazepam, IV, 4 mg, repeat once after 5–10 minutes, if necessary.

LoEI [32]

OR

  • Midazolam, IM/IV, 10 mg, repeat once after 5–10 minutes if necessary.

LoEI [33]

OR

  • Midazolam buccal, 10 mg using the parenteral formulation, repeat once after 5–10 minutes if necessary.

LoEIII

OR

  • Clonazepam, IV, 2 mg, repeat once after 5–10 minutes if necessary.

LoEIII [34]

If none of the above are available, consider:

  • Diazepam, IV, 10 mg, not faster than 2 mg/minute, repeat once after 5–10 minutes if necessary.

LoEI [35]

AND

  • Phenytoin, IV, 20 mg/kg diluted in 200 ml sodium chloride 0.9% (not dextrose) administered not faster than 50 mg/minute preferably with cardiac monitoring.
    • Avoid phenytoin if seizures are secondary to poisons with potential cardio-toxic effects.LoEII [36]
    • If arrhythmias occur, interrupt the infusion temporarily and reintroduce slowly.
    • If further/continued seizures, repeat a second phenytoin dose, IV, 10 mg/kg. LoEI [37]

Seizures continuing after 30 minutes:

Intubate and ventilate patient.

  • Thiopental, IV, 2–4 mg/kg, followed by 50 mg bolus every 2–3 minutes to control seizures.
    • Maintenance dose: 1–5 mg/kg/hour, depending on the presence of epileptogenic activity on EEG.
    • Beware of hypotension.
    • Once seizures are controlled for 24 hours, wean off thiopental by decreasing the dose by 1 mg/kg every 12 hours.

LoEIII [38]

OR

  • Propofol, IV, 1–2 mg/kg/dose as a bolus, followed by 2–10 mg/kg infusion, titrated to effect
    • Maintenance dose: 3–5 mg/kg/hour.

LoEIII [39]

OR

  • Midazolam, IV 0.1–0.2 mg/kg bolus, followed by 0.05–0.5 mg/kg/hour infusion, titrated to effect.

LoEIII [40]

Note:

  • Continue anaesthetic for 12−24 hours after the last clinical or electrographic seizure, then taper the dose. LoEIII [41]
  • Higher initial maintenance doses of phenytoin may be needed in patients who have had previous thiopental exposure.
  • After thiopental has been weaned off, use daily therapeutic drug monitoring to guide phenytoin doses, until phenytoin levels have stabilised. LoEIII [42]

MAINTENANCE THERAPY

Once seizures are controlled:

  • Phenytoin, IV/oral, 300 mg daily. LoEIII [43]
    • Adminster the first maintenance dose 12 hours after the loading dose.

Clinical signs that seizures are controlled include autonomic stability and the absence of abnormal movement.

For long-term maintenance therapy, see Epilepsy .