Introduction

Seizures are defined as transient occurrences of signs or symptoms related to abnormal excessive or synchronous neuronal activity in the brain. Acute seizures comprise approximately 1% of all emergency department visits. Acutely, most seizures are identified by motor symptoms, such as clonic jerking. The most common seizure emergencies are acute repetitive seizures, an abrupt increase in seizure frequency compared to baseline, and status epilepticus (SE), at least 30 min of continuous seizure activity or multiple seizures without return to neurological baseline. Convulsive seizures are easily recognized; however nonconvulsive seizures are less clear yet are present in nearly 20% of patients with altered mental status (AMS) who receive electroencephalography (EEG). A period of AMS occurring in the period following a seizure is referred to as a postictal state.

Signs/Symptoms

Seizures have a wide variety of possible manifestations, however common signs and symptoms include:

  • Mental status changes (confusion, amnesia, catatonia, psychosis, delirium, agitation, etc.)

  • Altered sensation (visual, gustatory, olfactory, etc.)

  • Convulsive motor activity (tonic contractures, clonic jerking)

Life-threatening Symptoms/Signs

  • Hyperthermia

  • Hypertension (though progresses to hypotension as status epilepticus progresses)

  • Cardiac arrhythmias

  • Rhabdomyolysis

Differential

Most seizures are unprovoked or occur from progression of symptomatic causes; however in hospitalized patients the vast majority of seizures or SE have an acute symptomatic cause. Potential causes include:

  • traumatic brain injury

  • stroke

  • hemorrhage

  • CNS infections or tumors

  • metabolic abnormalities (for example, hyponatremia)

  • alcohol withdrawal

  • Illicit substances and medications can also lower the seizure threshold

  • *Epileptic seizures should also be differentiated from psychogenic nonepileptic seizures

Testing

  • Laboratory studies should be directed but could include:

    • Basic metabolic panel, calcium, magnesium, phosphate to rule out metabolic causes

    • CBC

    • Liver function tests

    • Troponin

      Antiepileptic drug (AED) levels, particularly if patient is known to be prescribed an AED such as phenytoin or valproic acid

    • HCG level for women of reproductive age

  • Other studies:

    • EEG

    • Imaging (must balance the value of imaging with the cost of delaying treatment)

    • Lumbar puncture & cerebrospinal fluid analysis if safe to do so and there is suspicion for encephalitis or subarachnoid hemorrhage

Treatment

  • Airway management and respiratory support as indicated

  • Place patient in left-lateral decubitus position

  • Remove any foreign objects from mouth

  • Cardiac monitoring

  • Correct fluid and electrolyte imbalances

  • If hypoglycemic (<80 mg/dL) administer 100 mg of thiamine followed by 20–50 g of dextrose 50% solution

  • First line treatment for managing SE: benzodiazepines

    • Lorazepam—0.1 mg/kg at a rate of 2 mg/min

    • Midazolam—0.2 mg/kg, initial dose of 10 mg IM

    • Diazepam—0.2 mg/kg at a rate of 5 mg/min

  • Second line treatment: AEDs

    • Phenytoin—20 mg/kg IV loading dose at a rate 50 mg/min; 100 mg every 6–8 h maintenance dose

    • Valproate—20–40 mg/kg loading dose; 4–6 mg/kg every 6 h maintenance

    • Levetiracetam—2000–4000 mg loading dose; 10–15 mg/kg every 12 h maintenance

    • Lacosamide—200–400 mg loading dose; 200–300 mg every 12 h maintenance

  • Third line interventions for SE include propofol, pentobarbital, and ketamine

Tool

Potential Causes of Provoked Seizures

Drugs of Abuse

Alcohol

Stimulants

Ecstasy

Phencyclidine (PCP)

Lysergic acid diethylamide (LSD)

Infection/Inflammation

Meningitis

Encephalitis

Cerebritis

Lesions

Tumors

Stroke

Hemorrhage

Systemic

Eclampsia

Thyrotoxicosis

Extreme fever

Metabolic Disorders

Hypoglycemia, Hyperglycemia

Hyponatremia, Hypernatremia

Hypocalcemia

Hypomagnesemia

Antibiotics

Penicillins

Isoniazid

Rifampin

Antimalarials

Metronidazole

Antiarrhythmic agents

Digoxin

Lidocaine

Antidepressants

Bupropion

Cyclics

Antipsychotics

Clozapine

Haloperidol

Pain Medications

Tramadol

Demerol

Fentanyl

Miscellaneous Medications

Baclofen

Phenytoin (at supratherapeutic levels)

Calcineurin inhibitors (cyclosporine, tacrolimus)

Lithium

Chemotherapeutic agents

Multiple sclerosis medications

Withdrawal from

Opiates

Alcohol

AEDs (especially benzodiazepines and barbituates)

Trauma