Epilepsy

• Patients and families presenting with seizures are advised about safety precautions and recognising, managing and reporting further seizures. Safety precautions include:

  • The DVLA will remove their driving licence until specific criteria are met (being seizure-free for one year)
  • Taking showers rather than baths (drowning is a major risk in epilepsy)
  • Particular caution with swimming, heights, traffic and dangerous equipment
• Treatment of epilepsy depends on the type of seizure. Treatment aims to be seizure-free on the minimum anti-epileptic medications, ideally monotherapy with a single drug
• 1st line treatment for generalised tonic-clonic seizure:

  • Men and women who cannot have children - sodium valproate
  • Women of childbearing age - Lamotrigine or levetiracetam
• First line treatment for all patients with partial seizures is Lamotrigine or Levetiracetam
• Sodium valproate works by increasing the activity of gamma-aminobutyric acid (GABA) which has a calming effect on the brain
• Notable side effects of sodium valproate:

  • Teratogenic - causes neural tube defects and developmental delay
  • Liver damage and hepatitis
  • Hair loss
  • Tremor
  • Reduce fertility
• Status epilepticus is a medical emergency defined as either:

  • A seizure lasting more than 5 minutes 
  • Multiple seizures without regaining consciousness in the interim
• Management of status epilepticus involves an ABCDE approach, including:

  • Securing the airway
  • Giving high-concentration oxygen
  • Checking blood glucose levels
  • Gaining intravenous access (inserting a cannula)
• 1st line treatment of status epilepticus is a benzodiazepine (can be given again after 5-10 minutes if seizure continues):

  • Buccal midazolam
  • Rectal diazepam
  • IV lorazepam
• Epilepsy is a chronic neurological disorder characterised by recurrent seizures. Diagnosis is made when 2 or more unprovoked seizures more than 24 hours apart
• Acute symptomatic seizure secondary to a defined cause needs to be differentiated from the recurrent, unprovoked seizures that occur in epilepsy
• Epilepsy results from an imbalance between excitatory (glutamatergic) and inhibitory (GABAergic) neuronal signalling. This reduces the threshold for neurotransmission
• Seizures in the frontal lobe are associated with abnormal movements (pelvic thrusting, leg cycling) and vocalisation
• Seizures in the temporal lobe are associated with abnormal sensations like deja vu
• Seizures in the occipital lobe are associated with visual disturbances
• Structural abnormalities are a risk factor for epilepsy:

  • Head injury
  • Stroke
  • Space occupying lesions
  • Neurodegenerative diseases
• Provoked seizures are when there is a triggering event that causes the seizure to occur, due to reduced seizure threshold:

  • Acute stroke
  • Head trauma
  • Hypoglycaemia
  • Hyponatremia
  • CNS infection
  • Alcohol withdrawal
• Generalised seizures affect both cerebral hemispheres and are often motor. They always affect consciousness in some way:

  • Tonic-clonic (grand mal): stiffening followed by jerking. Complete loss of consciousness with a prolonged post-ictal period
  • Myoclonic: jerking movements
  • Atonic (drop attack): sudden loss of muscle tone often resulting in a fall
  • Absence seizure: vacant period where the patient is unresponsive. Muscle tone not usually affected
• Focal or partial seizures can be motor or non motor:

  • Often in the temporal lobe, affecting hearing, speech, memory and emotions
  • Simple partial seizure = remains awake
  • Complex partial seizure = lose awareness
  • Can spread to the contralateral hemisphere to become a generalised seizure
• Investigations for epilepsy:

  • Capillary blood glucose - hypoglycaemia
  • FBC - infection
  • U&Es - uraemia and hyponatraemia
  • VBG - lactate raised after tonic-clonic seizure
  • Neuroimaging - to rule out underlying structural cause
  • EEG
  • +/- lumbar puncture - CNS infection
• A focal seizure that involves tonic or clonic movements - will be unilateral on contralateral side
• Focal onset seizures are associated with automatisms which are repeated stereotyped movements such as lip smacking and pulling at clothes
• Enzyme inducing anti-epileptics such as carbamazepine and topiramate may reduce the efficacy of oral contraceptives
• Oestrogen containing contraceptives may reduce the effectiveness of lamotrigine
• Treatment of absent seizures is with Ethosuximide
• Status epilepticus management:

  1. Buccal midazolam or rectal diazepam if in community or IV lorazepam if access
  2. If no response after 5-10 minutes = give second dose
  3. If no response to 2 doses of benzodiazepines = IV loading with 2nd line AED - levetiracetam, phenytoin or sodium valproate
  4. If no response - consider using a different second line choice
  5. If no response - consider general anaesthesia with intubation and ventilation