Seizures

Question 1

The diagnosis of epilepsy is reserved for…

Answer 1

A syndrome recurrent, idiopathic seizures.

The ultimate cause of seizures in epilepsy is unknown.

Question 2

Causes of Seizures (four M’s, four I’s)

Answer 2

• Metabolic and electrolyte disturbances
  
  • Hyponatremia
  • Water intoxication
  • Hypoglycemia or hyperglycemia
  • Hypocalcemia
  • Uremia Thyroid storm
  • Hyperthermia
• Mass lesions
  
  • Brain mets
  • Primary brain tumors
  • Hemorrhage
• Missing drugs
  
  • Noncompliance with anticonvulsants
  • Acute withdrawal from alcohol, benzos, barbiturates
• Misc.
  
  • Pseudoseizures
  • Eclampsia –> only definitive tx is delivery but magnesium infusion is pharm tx of choice
• Intoxications
  
  • Cocaine
  • Lithium
  • Lidocaine
  • Theophylline
  • Metal poisoning (e.g. mercury, lead)
  • CO poisoning
• Infections
  
  • Septic shock
  • Bacterial or viral meningitis
  • Brain abscess
• Ischemia
  
  • Stroke
  • TIA (common cause in elderly pts)
• Increased ICP
  
  • For example: Due to trauma

Question 3

Types of epileptic seizures:

Answer 3

1. Partial
   
   1. Simple (no LOC)
   2. Complex (+LOC)
      
      1. Automatisms (last 1 to 3 min)–purposeless, involuntary, repetitive movements (such as lip smacking or chewing)
      2. Olfactory or gustatory hallucinations
2. Generalized
   
   1. Tonic-clonic (grand mal) seizure–b/l symmetric and without focal onset
      
      1. Begins with sudden LOC –> fall to the ground
   2. Absence (petit mal) seizure
      
      1. Typically involves school-age children (usually resolves)
      2. “Stare into space” - then return to activity
      3. Episodes are brief
      4. NO loss of postural tone or continence

Question 4

How to dx seizure - step by step

Answer 4

1. If pt has known seizure disorder, check anticonvulsant levels (one dose may be toxic for one pt & therapeutic for another)
2. If pt’s hx is unclear:
   
   1. CBC, electrolytes, blood glucose, LFTs, renal function tests, serum calcium, urinalysis
   2. EEG
   3. CT of head–to ID structural lesion
   4. MRI of brain–with and w/o gadolinium (first w/o)
      
      1. More sensitive than CT in identifying structural changes
   5. LP and blood cultures if pt is febrile

Question 5

Tx of seizures

Answer 5

1. ABCs!!!
2. Pt with hx of seizures (epilepsy)
   
   1. Usually due to noncompliance with anticonvulsant therapy
   2. If seizures persist, INC. dosage of first anticonvulsant until signs of toxicity appear. Add 2nd drug if seizures cannot be controlled w first drug.
   3. If seizures are controlled, have pt continue medication for at LEAST 2 years… then can taper.
3. First time seizure
   
   1. EEG & neurology consult.
   2. Anticonvulsant therapy
   3. Do NOT tx pts with single seizure… antiepileptics are started if EEG is. abnormal, brain MRI is abnormal, pt is in status epilepticus.

Question 6

Anticonvulsant agents

Answer 6

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!

Question 7

What to always remember before prescribning anticonvulsants?

Answer 7

Do pregnancy test!

Anticonvulsants = teratogenic.

Question 8

Status Epilecticus

Answer 8

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)

Question 9

Best way to test for seizure recurrence

Answer 9

Sleep deprivation EEG