Neurology Flashcards
(107 cards)
What is a seizure?
Transient occurrence of signs or symptoms due to abnormal excessive or synchronous neuronal activity in brain
Can be a disturbance of consciousness, behaviour, cognition, motor function or sensation
What is epilepsy?
Neurological disorder where person experiences recurring seizures
How is epilepsy defined?
At least 2 unprovoked seizures occurring >24h apart
Diagnosis of epilepsy syndrome
One unprovoked seizure and a probability of further seizures
RF for epilepsy
premature birth
complication febrile seizures
genetic conditions - tuberous sclerosis or neurofibromatosis
FHx of epilepsy or neurological illness
Head trauma, infections (meningitis/encephalitis) or tumours
Comorbid conditions: cerebrovascular disease and stroke
Dementia and neurodegenerative disorders (Alzheimers)
Aetiology of Epilepsy
Structural: abnormalities such as stroke, trauma or malformation of cortical development
Genetic
Infectious: TB, HIV, cerebral malaria, congenital infections
Metabolic: porphyria, pyrixodine deficiency
Immune: anti-NMDA receptor encephalitis and anti-LG11 encephalitis
PC for epilepsy/different types of seizure
Short-lived abrupt generalised muscle stiffening with rapid recovery = tonic seizure
Generalised stiffening and subsequent rhythmic jerks of limbs, urinary incontinence, tongue biting = generalised tonic-clonic seizure
Behavioural arrest = absence seizure
Sudden onset of loss of muscle tone = atonic seizure
Brief, shock-like involuntary single or multiple jerks = myoclonic seizure
Causes of seizure
Epilepsy
Vasovagal
Cardiac arrhythmias
Panic attacks with hyperventilation
NEAD
TIA
Migraine
Meds, alcohol, drug intoxication
hypoglycaemia
movement disorders
sleep disorders - narcolepsy, sleep apnoea
Delirium/dementia - altered awareness
Children: febrile convulsions, breath-holding attacks, night terrors, ritualistic behaviours
Triggers for seizures
Sleep deprivation
Stress
Light sensitivity
Alcohol use
Acute Mx of a tonic-clonic seizure <5m
Check for epilepsy identity card or jewellery
Protect for injury: cushion head, remove glasses
do NOT restrain them or put anything in mouth
When stops check airway and put in recovery position
Observe until recovered
Examine for any injuries
Call ambulance: if first seizure, another reoccurs shortly after first, person is injured, struggling to breathe or difficult to wake
Mx of tonic-clonic seizure >5m
OR >3 seizures in an hour
Buccal midazolam 1st line in community
Rectal diazepam if preferred or midazolam not available
IV lorazepam if IV access
Can an ambulance
When to call an ambulance for seizure?
If >5m
If first seizure
If seizure were prolonged to recurrent before treatment - status epilepticus
high risk of recurrence
hx of repeated seizures or status epilepticus
When can you stop prescribing AEDs?
Under specialist supervision if patient is seizure free >2y
Routine Mx for focal seizures
1st line = carbemazepine/lamotrigine
2nd line = levetiracetam, oxycarbazepine or sodium valproate
Mx of generalised tonic-clonic seizures
1st line = sodium valproate or lamotrigine
2nd line = carbemazepine, clobazam, levetiracetam or topiramate
Mx of absence seizures
1st line = sodium valproate or ethosiximide
2nd line = lamotrigine
Mx of myoclonic seizures
1st = sodium valproate
2nd = levetiracetam or topiramate
AVOID carbamazepine and oxycarbazepine as worsen seizures
Tonic or atonic seizures
sodium valproate or lamotrigine
Status epilepticus
Medical emergency
seizure lasting .5m
multiple seizures without regaining consciousness in interim
Mx of status epilepticus
ABCDE
Secure airway
giving high-flow oxygen
check CBG
Gain IV access
1st line = BDZs (buccal midazolam 10mg, rectal diazepam 10mg, IV lorazepam) repeat after 5-10mins if seizure continues
2nd = after 2 doses of BDZs are IV levetiracetam, phenytoin or sodium valproate
3rd = phenobarbital or GA
Causes of stroke
Small vessel occlusion/cerebral microangiopathy/thrombosis
Cardiac emboli (AF, endocarditis, MI)
Atherothromboembolism (e.g from carotids)
CNS bleeds (increased BP, trauma, aneurysm rupture, anticoagulation, thrombolysis)
What do cerebral infarcts look like clinically?
Contralateral sensory loss or hemoplegia
Initially hypotonic progressing to hypertonic
Dysphasia
Homonymous hemianopia
Visuo-spatial deficit
What do brainstem infarcts look like clinically?
Quadriplegia
Disturbances of gaze and vision
Locked in syndrome
Clinical presentation of lacunar infarcts
infarcts in basal ganglia, internal capsule, thalamus and pons
ataxia hemiparesis
pure motor/sensory
sensorimotor
dysarthria/clumsy hand
cognition and consciousness are intact except thalamic stroke
Silent stroke
radiological or pathological evidence of an infarction without an attributable hx of acute neuro dysfunction