Neuro - Acute management and theory of epilepsy Flashcards
Management of epilepsy: outline the algorithm for seizure management
- A-E assessment + test glucose
- IV lorazepam 4mg (wait 5-10 mins)
- IV lorazepam 4mg (wait 5-10 or until patient is in established status epilepticus)
- Phenytoin infusion 20mg/kg at a max rate of 50mg/min + call ITU when decision is made to use phenytoin
- Anaesthetists arrive and perform rapid sequence induction with thiopental
*If IV access not possible: 10mg IM midazolam or 4mg Rectal diazepam
What is the definition of status epilepticus?
> 5 mins of continuous seizure or 2+ seizures without full recovery within 30 minutes
Outline some important tasks you should be performing whilst managing a patient in status epilepticus
- Find and read notes
- Ask nursing staff lorazepam + phenytoin (takes a while to prepare)
- A-E assessment
- Cannula + bloods (U+E, LFT, FBC, CRP, cultures, glucose, clotting screens anti-epileptic medication levels (if known epileptic) + toxicology screen (urine)
- ABG (look at blood glucose)
- Assign someone to keep time
- Administer O2
What tasks should you perform post seizure? Should you offer neuro-imaging?
- Give pabrinex (if relevant) + IV fluids
- Chase blood results
- Attempt Hx + collateral
- CT head, blood cultures, blood alcohol level
Neuroimaging is not routinely done for idiopathic generalised epilepsy (people are allowed 1 seizure) - indications for imaging:
- Onset of epilepsy as adults
- Evidence of focal onset
- Seizure continuing despite 1st line tx (lorazepam)
What is the definition of a seizure?
-Paroxysmal, synchronous and excessive discharge of neurones in the cerebral cortex manifesting as a stereotyped disturbance in consciousness, behaviour, emotion, motor function or sensation. It is if sudden onset, last secs-mins, usually ceases spontaneously and may recur.
What is the difference between epilepsy and acute symptomatic seizures?
- Epilepsy: condition where there is a propensity to have recurrent and unprovoked seizures
- Seizures occurring solely in association with precipitants (fever in kids, metabolic disturbance, alcohol/drug abuse, acute head injury) are treated differently.
Name some risk factors for seizures
- > 50% have no cause found
- Childhood and adolescence (idiopathic)
- HTN: 50-70ya
- Vascular changes, alcohol abuse, tumours, head injury
- +ve FHx
- Withdrawal of AEPs
- Infectious causes: encephalitis, meningitis
What are focal seizures?
- Arise from localised areas of cerebral cortex
- 60% arise from temporal lobes, rest mainly from frontal lobes
What are the features of a temporal lobe seizure?
- Aura: epigastric sensation, olfactory/gustatory hallucination, autonomic sx (change in BP/pulse), affective sx (fear) and deja vu
- Seizure: motor arrest, absence, automatisms (lip smacking, fidgeting, chewing)
- Lasts 1-2 mins
- Post-ictal confusion is common
What are the features of a frontal lobe seizure?
- Aura: abrupt onset with variable aura (indescribable), forced thinking, ideation always or emotional manifestations
- Seizure: vocalisations/shrill cry, violent/sexual/bizarre automatisms, cycling of legs
- Very brief seizure eg 30s
- Post-ictal confusion is brief with rapid recovery
What are the features of a parietal lobe seizure?
- Somatosensory symptoms common:paraesthesia, numbness, prickling, vertigo, distortions of space
- Automatism and secondary generalisation may occur
What are the features of a occipital lobe seizure?
- Visual hallucinations common: flashing lights, geometrical figures, complex hallucinations of objects/people
- May get automatisms and secondary generalisation
What is a focal aware seizure?
- Consciousness not impaired (localised discharge)
- Typically brief with focal sx
- Ensure to rule out structural brain lesion (stroke, tumour, abscess)
What is a focal seizure with impaired awareness?
- Similar sx to focal aware but need impairment of consciousness (but without loss of postural control - pt remains standing)
- Usually 2-3 mins but can be hours
- Pt usually amnesic of event
What are the types of generalised seizures?
- Tonic-clonic
- Absence
- Myoclonic
- Atonic
- Tonic
What are the features of a tonic-clonic seizure?
- Usually no warning - may be preceded by increasing frequency of myoclonic jerks - LoC and pt falls to ground
- Tonic phase: 10 sec - stiff body, flexed elbows and extended legs
- Clonic phase: 1-2 mins of violent generalised shaking, open and rolled back eyes, tongue bitting +/- incontinence
- Postictal confusion: v difficult to rouse, headaches, myalgia and retrograde amnesia
What are the features of a absence seizure?
- Typical onset between 4-14 ya
- Attacks can occur several times per day, last 5-15 s - patient suddenly stares vacantly +/- eye blinking and myoclonic jerks
- Diagnosed after complained of inattentive child - EEG shows 3per second spike and wave complexes
- Atypical absences seizures are associated with more severe epileptic syndromes (eg Lennox-Gastaut)
What are the features of a myoclonic seizure?
Abrupt, brief involuntary movements of some or all parts of the body
*Not all myoclonus is a result of epilepsy
What are the features of a atonic and tonic seizures?
- Rare, generalised seizures (drop attacks) in severe epilepsy syndromes
- Atonic: sudden loss of postural muscles - pt falls
- Tonic: sudden increase in muscle tone - pt becomes rigid and falls
What is idiopathic generalised epilepsy?
- Group of epileptic disorders that are believed to have a strong underlying genetic basis (often have fhx of epilepsy), typically manifests between early childhood and adolescence
- Patients typically otherwise normal and have no structural brain abnormalities
- Seizures: absent, myoclonus, and primary generalised tonic-Clonic
- Risk factors: sleep deprivation and alcohol
