Seizures Flashcards
Day 7
What are some provoked and unprovoked reasons for seizures?
Provoked - hypoglycaemia, alcohol withdrawal, low sodium, infection, fever, concussion
Unprovoked - stress, sleep deprivation, epilepsy, no cause
Define epilepsy
Common neurological condition
What is the pathophysiology of seizures ?
Neurons normally transmit electrical impulses to each other in a co-ordinated manner. In epilepsy sudden bursts of electrical activity occurs, causing spontaneous firing in an un-coordinated way this sudden, uncontrolled depolarisation of neurons results in abnormal motor or sensory activity with or without loss of consciousness.
The exact cellular activities that initiate seizure are not completely clear, however theories of specific mechanisms for seizure activity include altered permeability of the neuronal membrane, reduced inhibitory neuronal control or imbalance of neurotransmitters. Alterations in ions and neurotransmitters result in hyperexcitation and loss of inhibitory neurons give rise to hyper-synchronicity which can result in partial or generalised seizure depending on its spread
of activity.
Define the different types of seizures
Focal - (partial) - erratic electrical activity starts in well defined area of brain.
Generalised seizure - immediate onset of widespread electrical activity across the whole brain.
Non epileptic seizures - organic (physical cause) or psychogenic (psychological cause) not as a result of erratic electrical conductivity.
What are the types of partial / generalised seizures ?
Partial - simple, complex
Generalised - absence, myoclonic, tonic-clonic, tonic, atonic
Describe a simple focal seizure
Erratic electrical discharge in a localised part of the brain and does not impair consciousness.
Symptoms include:
‘Strange’ feeling
Unsettled stomach sensation (eg: rollercoaster)
déjà vu
Unusual smell or taste
Tingling in the arms/legs
Feeling of fear or joy
Stiffness/Twitching of one part of the body (eg: an arm)
The person remains conscious and aware of what is happening
May now be referred to as “focal onset aware seizure”.
Describe a complex focal seizure
Erratic electrical activity in a localised part of the brain, but consciousness is impaired
Symptoms:
Smacking lips
Rubbing Hands
Making noises
Moving arms around
Picking at clothes
Chewing or Swallowing
The patient will have loss of awareness
May be referred to as “Focal Onset Awareness Impaired Seizure”.
How does a focal seizure lead to a secondary generalised seizure ?
Erratic electrical activity occurs in localised part of brain, with impaired consciousness, erratic electrical activity becomes widespread. Patients may experience an aura before progressing onto next seizure (symptoms like simple focal seizure).
What is an absence seizure ?
Widespread erratic electrical activity; the patient looses awareness for a short time and looks ‘blank’
Symptoms:
Staring blankly into space
‘Daydreaming’
Fluttering eyes
Very slight jerking of the limbs
Has previously been misinterpreted as a child who regularly ‘daydreams’
Normally last for a very short period 10-15 seconds
Normally has an immediate recovery
May also be categorised as ‘atypical’ if features are different or last longer
Used to be known as “petite mal”
No treatment necessary; except for maintaining safety and reassurance
What is a myoclonic seizure ?
Widespread erratic electrical activity, causing jerk like movements of limbs and body. Patient normally conscious. Sometimes can occur in several times in quick succession. Immediate treatment not required but should be managed by physician.
What is a tonic colonic seizure ?
Complete widespread full erratic electric activity across the brain
Used to be known as a “grand mal” seizure
Occurs in two stages:
1: ‘Tonic Stage’: The patient looses consciousness, body goes stiff, and will fall to the floor if standing upright
2: ‘Clonic Stage’: Rapid violent jerking of the limbs, incontinence, biting of the tongue/cheek, signs of hypoxia
Normally last for 2-3 minutes
Patient may be tired, confused, irritable, or have low mood immediately after the seizure – some may remain unconscious whilst they recover (this is known as the post-ictal state)
Management:
Airway – Turn the person onto their side; may need an nasopharyngeal airway inserted during the seizure; or an NP/OP airway if remaining unconscious when post-ictal
Breathing – Immediately commenced 15L High Flow Oxygen via non-rebreather mask
Once seizure has stopped, use the ABCDE approach to assess the person if unconscious post-ictal
If conscious after the seizure, maintain safety and reassure
What is status epilepticus ?
Ongoing state of widespread erratic electrical activity, following this criteria:
If a tonic-clonic seizure has lasted over 10 minutes OR
If there have been 3 seizures without recovery in a row
This is a medical emergency – 999 / Crash Team
When is a tonic clonic an emergancy?
The person is not epileptic or had this type of seizure before
The seizure lasts more than 5 minutes
What are the risk factors associated with epilepsy ?
Non adherence to medication
Alcohol and drug misuse
Previous CNS infection
Having uncontrolled seizures
Previous brain injury
Previous stroke
Abnormal neurological examination findings
Having focal to bilateral tonic-clonic seizures or generalised tonic-clonic seizures
Metastatic cancer
How are non epileptic seizures categorised ?
Organic - physical or medical cause, resolve when medical cause is found.
Psychogenic - caused by emotional processes or psychological health.
