Primary care - Neurological Flashcards
(104 cards)
What is epilepsy?
Recurrent tendency to spontaneous, intermittent, abnormal electrical activity in part of the brain, manifesting as seizures
- general=both hemispheres
- focal=one area within 1 hemisphere
What causes epilepsy?
2/3rd = idiopathic
1/3rd have identified cause:
- Space-occupying lesion e.g. neoplasm
- Head injury or cortical scarring from previous head injury
- CNS infections
- Stroke
- Hippocampal sclerosis after febrile convulsion
- Vascular malformations
What are some triggers of seizures?
Stress
Flashing lights
Alcohol/alcohol withdrawal
What are the common features of focal/partial seizures?
-focal motor/sensory (olfactory-smells, visual-flashing lights) /autonomic/psychic (change in mood/behaviour) symptoms
What is a focal/partial seizure?
3 types of focal/partial seizure?
Start in one area of one side of the brain. Often seen with underlying structural disease
3 types:
1. Without impairment of consciousness ‘simple’:
- With impairment of consciousness ‘complex’
- most commonly temporal lobe
- post-ictal confusion (headache, confusion, myalgia, temporary weakness, dysphasia) - Focal to bilateral tonic-clonic seizure (2/3s progress to generalised seizure-convulsive)
What are generalised seizures?
What are the different types and how do they present?
What features are present for all of these?
Involve both hemispheres of the brain
- Tonic-clonic - LOC, stiff limbs (tonic) then jerk (clonic). Tongue biting, incontinence. Post-ictal confusion and drowsiness
- Absence seizures - brief (less than 10 sec) pauses e.g. stares into space for 5 seconds then resumes talking, common in childhood
- Myoclonic - sudden shock like jerk of limb/trunk/face
- Atonic - all muscles relax and drop to floor, no LOC
What investigations should you do in epilepsy? (bedside, bloods, imaging, special)
EPILEPSY
Bedside
-ECG-1st line for all adults
• arrhythmia or long QT
Bloods
-for acquired causes: FBC, U&E, LFTs, Glucose, Ca2+
Imagning
MRI - if new Dx in adults to exclude infective or vascular causes (do not do routinely)
Special tests
-EEG
•after 2nd seizure or 1st if considered necessary by neurologist
•should add to clinical diagnosis (cannot exclude epilepsy)
What are DVLA guidelines related to seizures?
Inform DVLA:
• 1st unprovoked seizure – stop driving for 6 months.
• Epileptic seizure – stop driving until seizure-free for 1 year.
• No HGV driving until seizure free and no meds for 10 years
What are 1st line treatment for focal/partial seizures?
1st line - carbamazepine or lamotrigine
2nd line - sodium valproate
Extra info:
Prescribe brand name - changing brand has 10% risk of worse seizure control
AEDs can only be prescribed following confirmed diagnosis (usually after second
seizure)
Patients on AEDs are entitled to free prescriptions
What are 1st line treatment for all generalised seizures?
Sodium valproate
second line is normally lamotrigine (unless absence)
What type of seizures should you AVOID carbamazepine in ?
Carbamazepine can worsen:
Absence
Myoclonic (if sodium valproate CI>2nd line levetiracetam)
Which anti-epileptic drug must be strictly avoided in pregnancy?
What should they take instead?
Sodium valproate is the most teratogenic (do not give if sexually active or pregnant)
Lamotrigine is preferred
What are the side effects of sodium valproate?
vALPROATE
Appetite increase - weight gain Liver failure Pancreatitis Reversible hair loss - grows back curly Oedema Ataxia Teratogenicity, thrombocytopenia, tremor Encephalopathy
Which drug should you avoid if taking sodium valproate?
Aspirin - it displaces sodium valproate from its binding sites which increases the adverse effects
When is carbamazepine contraindicated?
AV node conduction abnormalities
Bone marrow depression
Define stroke and TIA - specifying the differences
Stroke = sudden onset of focal/global neurological disturbance lasting over 24 hours. Causes irreversible cell damage + death.
TIA = less than 24 hour neurological dysfunction caused by ischaemia
What heart diseases particularly predispose you to ischaemic stroke?
AF
Infective endocarditis
Valve disease
Heart failure
What are some causes of stroke?
- Most common is atherosclerotic plaque aetiology
- Haemorrhage: aneurysm rupture, SAH,HTN, trauma
- Carotid artery dissection (most common cause of ischimic stroke in young people)
- Cerebral embolism (from AF, endocarditis, MI)
What is the most common cause of ischaemic stroke in young people?
Carotid artery dissection - usually caused by hitting their chin and hyperextending their neck, rupturing the carotid artery
What symptoms point more towards a bleed than ischaemia?
Meningism
Severe headache
Coma
Seizure
What does the anterior cerebral artery supply?
How would an anterior cerebral artery stroke present?
ACA supplies frontal + medial side of cerebrum
(medial side supplies legs (think homunculus)
-Contralateral leg weakness and sensory loss (lower limb>upper limb (FOOT DROP)
- personality change/depression
- urinary incontinance
What does the middle cerebral artery MCA supply?
How would an middle cerebral artery stroke present? (4)
-MCA supplies lateral side of cerebrum
- Contralateral weakness and sensory loss (upper limb>lower limb) effecting ARMS more
- Contralateral homonymous hemianopia
- If DOMINANT HEMISPHERE then aphasia (e.g. left side for most people)
- If NON DOMINANT HEMISPHERE then affects neglect (the patient will neglect the opposite side to the hemisphere)
How would a total anterior circulation stroke (TACS) present?
What artery occlusion normally causes this?
TACS (total anterior circulation stroke) includes the ACA and MCA
ALL 3 OF FOLLOWING
- Unilateral weakness (and or sensory) of face, arm, leg
- Higher cerebral dysfunction (dysphasia, visuospatial)
- Homonymous hemianopia (if involving optic radiation)
If partial, then 2/3 are present
How does a posterior circulation stroke (POCS) present? (6)
Either one of the following:
- Cranial nerve lesions with contralateral motor/sensory deficit
- Eye movement disorder (gaze palsy)
- Isolated homonymous hemianopia (posterior cerebral artery)
- Loss of conciseness
- Cerebral/brainstem syndrome (coordination/ataxia)
- Bilateral motor/sensory defect