Differential Diagnosis of Paroxysmal Disorders – adapted from Tintinalli’s Emergency Medicine: A Comprehensive Guide
- CNS
- Seizure
- Syncope
- Migraines
- TIAs
- Neuromuscular
- Movement disorders (dystonia, myoclonic jerks, chorea, tremor, tics)
- Psychiatric
- Pseudoseizure
- Narcolepsy
- Cataplexy (drop attacks)
- Hyperventilation syndrome
Etiology of seizures
D rugs – side-effects, overdose, illicit
I nfection – CNS, febrile type
M etabolic – ↑/↓glucose, ↑/↓sodium, hyperosmolar, uremia, hepatic failure hypocalcemia, hypomagnesemia
W ithdrawal – EtOH – delirium tremens
I ntracranial hemorrhage
T rauma
S tructural – congenital, vascular, mass, degenerative
S leep deprivation
P regnancy eclampsia
Classification
Generalized – loss of consciousness, whole cerebral cortex activation (tonic-clonic, tonic, clonic, myoclonic, atonic, absence, febrile)
Partial – no loss of consciousness, localized activation of cortex (simple partial, complex partial, *may have 20 generalization)
History
Most patients present to the emergency room after their “seizure” has finished. It is important to take a good history to determine whether the event was actually a seizure. Information may be gathered from the patient themselves, as well as descriptions of the patient’s attack from those who witnessed the event.
- HPI
- Preceding symptoms: aura
- Event: onset, activity, sphincter control, duration
- Postictal: confusion, lethargy, recovery, recollection of event, Todd’s paralysis
- ? ingestions, ?precipitants, ?extent of trauma, ?focality
- PMHx
- Known seizure disorder – diagnosis, prior seizures, baseline, triggers, antiepileptics (missed or changes in Rx)
- Infection
- Trauma
- Sleep
- Metabolic
- Unknown seizure disorder – school/work, injuries unexplained, sphincter control
- Drugs – EtOH, illicit Rx, withdrawal
- Pregnancy
- FHx
Physical Exam
- Vitals (especially temperature and glucose)
- Look for injuries (orthopedic, oral)
- Look for infection
- Neurological examination
- Dermatologic exam (especially in pediatrics – look for ash leaf spots, café au lait spots, port wine stains…)
Investigations – use clinical judgement based on patient’s presentation and history
- Blood glucose
- CBCD
- Electrolytes, BUN, creatinine, calcium, magnesium, anion gap, lactate, prolactin (will be elevated after seizure, sometimes used if not sure if event was a seizure)
- Beta-HCG
- ABG, U/A, LP
- Toxicology
- Anticonvulsant levels
- CK – for rhabdomyolysis (urine shows Hgb but no RBC)
- CT head if trauma, suspected intracranial hemorrhage, suspected structural lesion in first time seizure, prolonged altered mental status, focal neurological deficit, anticoagulated patient, HIV/Cancer patients, ongoing H/A, change in seizure pattern
- If infection – may require full septic w/u (LP, cultures, etc)
- EEG – most likely to be done as an outpatient
- MRI – in consultation with neurology
- Don’t forget to investigate for suspected injuries as a result of the seizure!
Treatment
- If the patient is seizing
- Move to safe place
- Turn to side (recovery position) if possible
- Observation for specific activity and progression and duration
- Prepare to assess/monitor once seizure subsides (ABC’s)
- Consider treatment if patient is in status
- Postictal
- Seizure precautions
- ABC’s and monitors, chemstrip, O2
- Benzodiazepines may be used to prevent further seizures
- Consider anticonvulsant therapy
- Phenytoin (Dilantin) 300-600mg PO tid
- Phenobarbital 60-200mg PO daily
- Valproic acid (Epival) 15-60mg/kg daily divided bid or tid
- Carbamazepine (Tegretol) 400-1200mg daily divided tid/qid
- Status epilepticus – 30+min of active seizing or no recovery/consciousness between
- IV line, O2, monitors
- Consider intubation
- Benzodiazepines (diazepam 10-20mg IV, or lorazepam 4-8mg IV)
- Phenytoin 18-20mg/kg IV @ 25mg/min
In first time seizures with normal EEGs approximately 25% will seize again within 2 years. In first time seizures with abnormal EEGs, it rises to 50%. Also mortality is unchanged with medication.
PREVENTION!!!
- No driving for 1 year
- Warn about swimming and heights