Seizures Flashcards
The diagnosis of epilepsy is reserved for…
A syndrome recurrent, idiopathic seizures.
The ultimate cause of seizures in epilepsy is unknown.
Causes of Seizures (four M’s, four I’s)
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Metabolic and electrolyte disturbances
- Hyponatremia
- Water intoxication
- Hypoglycemia or hyperglycemia
- Hypocalcemia
- Uremia Thyroid storm
- Hyperthermia
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Mass lesions
- Brain mets
- Primary brain tumors
- Hemorrhage
-
Missing drugs
- Noncompliance with anticonvulsants
- Acute withdrawal from alcohol, benzos, barbiturates
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Misc.
- Pseudoseizures
- Eclampsia –> only definitive tx is delivery but magnesium infusion is pharm tx of choice
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Intoxications
- Cocaine
- Lithium
- Lidocaine
- Theophylline
- Metal poisoning (e.g. mercury, lead)
- CO poisoning
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Infections
- Septic shock
- Bacterial or viral meningitis
- Brain abscess
-
Ischemia
- Stroke
- TIA (common cause in elderly pts)
-
Increased ICP
- For example: Due to trauma
Types of epileptic seizures:
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Partial
- Simple (no LOC)
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Complex (+LOC)
- Automatisms (last 1 to 3 min)–purposeless, involuntary, repetitive movements (such as lip smacking or chewing)
- Olfactory or gustatory hallucinations
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Generalized
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Tonic-clonic (grand mal) seizure–b/l symmetric and without focal onset
- Begins with sudden LOC –> fall to the ground
-
Absence (petit mal) seizure
- Typically involves school-age children (usually resolves)
- “Stare into space” - then return to activity
- Episodes are brief
- NO loss of postural tone or continence
-
Tonic-clonic (grand mal) seizure–b/l symmetric and without focal onset
How to dx seizure - step by step
- If pt has known seizure disorder, check anticonvulsant levels (one dose may be toxic for one pt & therapeutic for another)
- If pt’s hx is unclear:
- CBC, electrolytes, blood glucose, LFTs, renal function tests, serum calcium, urinalysis
- EEG
- CT of head–to ID structural lesion
- MRI of brain–with and w/o gadolinium (first w/o)
- More sensitive than CT in identifying structural changes
- LP and blood cultures if pt is febrile
Tx of seizures
- ABCs!!!
- Pt with hx of seizures (epilepsy)
- Usually due to noncompliance with anticonvulsant therapy
- If seizures persist, INC. dosage of first anticonvulsant until signs of toxicity appear. Add 2nd drug if seizures cannot be controlled w first drug.
- If seizures are controlled, have pt continue medication for at LEAST 2 years… then can taper.
- First time seizure
- EEG & neurology consult.
- Anticonvulsant therapy
- Do NOT tx pts with single seizure… antiepileptics are started if EEG is. abnormal, brain MRI is abnormal, pt is in status epilepticus.
Anticonvulsant agents
For generalized tonic-clonic seizures and partial seizures:
Phenytoin and carbamazepine = drugs of choice!
For petit mal (absence) seizures:
Ethosuximide and valproic acid = drugs of choice!
What to always remember before prescribning anticonvulsants?
Do pregnancy test!
Anticonvulsants = teratogenic.
Status Epilecticus
prolonged, sustained unconsciousness with persistent convulsive activity in a seizing pt
MEDICAL EMERGENCY
Mgmt: establish airway –> give IV diazepam, IV phenytoin, 50 mg dextrose
If seizure persists, then give phenytoin or fosphenytoin. If this doesn’t work –> phenobarbital.
Finally, ultimate therapy = succinylcholine, vecuronium, or pancuronium –> allow you to intubate pt and then give general anesthesia (midazolam or propofol)
Best way to test for seizure recurrence
Sleep deprivation EEG