Seizure without Status Epilepticus
Background
- Risk factors: birth trauma, perinatal ischemia, prematurity, TBI with loss of awareness > 1 hour or penetrating wound, strokes, brain masses, prior CNS infections, and recent brain surgery.
- Typical semiology: rhythmic, stereotyped event with sudden onset/offset.
- If bilateral seizure-like activity, then there will also be loss of awareness.
- If focal, can have loss of awareness or retained awareness.
Evaluation
- A clear description or recording of seizure semiology is helpful, including preceding aura, event description, duration, level of awareness, post-ictal confusion with duration, tongue biting (and location), urination/defecation, frequency of events, and triggers.
- Provoked seizures can develop with new medications (lower threshold), ASM/benzodiazepine/EtOH withdrawal, physical/mental/emotional stressors, significant electrolyte or glucose abnormalities, CNS infections.
- In pts with new seizures, important to work up potential underlying etiology.
- If patient has a known seizure disorder with a reversible underlying trigger or typical frequency of seizures and has returned to their baseline neurologic exam, EEG may not be necessary.
- In patients with new first-time seizures who have returned to baseline, would be reasonable to perform EEG in the outpatient setting if there is not a clear reason that the patient would be at risk for a repeat seizure (eg alcohol withdrawal).
- MRI brain with and without contrast with epilepsy protocol once stable.
Management
- You do not need to acutely treat a seizure with medication unless there is concern for status epilepticus, generalized tonic clonic activity lasting 5 minutes or greater.
ASM | Adverse Effects |
|---|---|
| Levetiracetam (Keppra) (PO/IV) | Sedation and agitation, worsening of underlying mood disorders. Can trial B6 supplementation to help with mood effects |
| Valproic acid (Depakote) (PO/IV) | Sedation, hirsutism, PCOS, P450 inhibitor, nausea, liver injury, hyperammonemia, teratogenicity |
| Phenytoin (Dilantin) (PO)/ Fosphenytoin (IV) | Sedation, gingival hyperplasia, arrhythmias |
| Lacosamide (Vimpat) (PO/IV) | Heart block, dizziness, ataxia |
| Topiramate (Topamax) (PO) | Kidney stones, metabolic acidosis, paresthesias, weight loss, cognitive slowing |
| Carbamazepine (Tegretol) (PO) / Oxcarbazepine (Trileptal) (PO) | Hyponatremia, SJS (in Han Chinese check HLA), bone marrow suppression (rare) |
| Lamotrigine (Lamictal) (PO) | SJS/TEN, nausea, least sedating |
| Zonisamide (Zonegran) (PO) | Sedation, ataxia, nausea, confusion |
Non-Epileptic Events (NEE)
- Can be difficult to distinguish from epileptic seizures.
- Not all NEE are psychogenic, such as myoclonus, tremors, and syncope.
- Features more common in PNEE.
- Retained awareness with bilateral extremity involvement.
- Opisthotonus (arching the back), truncal thrusting.
- Excessively long events (e.g. lasts hour or days).
- Forced eye closure.
- Coachability during an event or reacting to external stimuli.
- Immediately returning to baseline after an event.
Features more common in epileptic seizures:
- Seizures arising out of sleep.
- Highly stereotyped.
- Incontinence.
- Severe injuries (e.g. burns).
Management
- Try to avoid excessive BZD use that could compromise airway protection.
- This requires good clinical judgement as you wouldn't want to withhold Ativan and discover that the pt was having true atypical seizures. The compromise would be to not repeatedly administer BZDs when there is suspicion for PNEE as well as no evidence of response to prior BZD administration.
Syncopal Convulsions
- Very common, can present with posturing and tonic-clonic movements happening for a few moments after syncope.
- Should not last for more than 30 seconds.
- Do not typically require seizure medications.
- Can be associated with urinary incontinence.
- Workup.
- Two-hour EEG and MRI (with and without contrast).
- Infectious workup, BMP, CBC, blood glucose, toxicology/drug screen.
- Check orthostatic vitals.