Neurological Problems Flashcards
What are the different types of neurological problems
- Epilepsy
- Migraines and headaches
- Multiple sclerosis
- Myasthenia Gravis
- Myotonic dystrophy
- Idiopathic intracranial hypertension (idiopathic)
- Stroke
- Bell’s palsy
- Subarachnoid haemorrhage
- Cerebral vein thrombosis
- Posterior reversible encephalopathy syndrome
- Entrapment neuropathies
What is epilepsy?
- seizure (neurons synchronously active) disorder
- A neurological condition characterised by recurrent seizures
- Seizure are due to brief distributions in the electrical functions of the brain
- Caused by abnormal electrical discharge of cortical neurones (nerve cells)
- During a seizure clusters of neurons in the brain become temporarily impaired and starts to suddenly send excitatory signals over and over- paroxysmal.
- This occurs due to either too much excitation or too little inhibition.
Why do epileptic fits happen?
- Idiopathic
- Physical causes: head injury, cerebral tumours, stroke, hypertension, infection
- Metabolic causes: hyperglycaemia, hypoxia, uraemia, fluid and electrolyte imbalance, hyper or hyponatraemia
o Metabolic anomalies: Alteration in cell membrane properties due to abnormal blood concentrations on various ions/electrolytes - Syndromes: Antiphospholipid, Alzheimer’s, Wernicke-Karsakoff (thiamine B1 deficiency), Wilson’s disease
- Congenital defects: cerebral palsy, intracranial cysts
- Infection
- Postdural puncture
- Gestational epilepsy (idiopathic)
- Pseydoepilepsy/ non-epileptic seizure disorder
- Eclampsia
- Cerebral Vein thrombosis
- Thrombotic Thrombocytopenic purpura (TTP)
- Stroke
- Subarachnoid haemorrhage
- Drugs and alcohol (withdrawal)
What are the different types of fits?
Partial fits
- Simple partial
- Complex partial
- Secondary generalised
Generalised seizures: whole brain
- Absence
- Myoclonic
- Tonic
- Atonic
What are the partial fits?
commonly affects temporal lobe
o Simple partial: remain conscious, experience and aura, change in the way things look, smell, taste or sound, pins and needles in the arm, déjà vu.
o Complex partial: change in awareness, loses memory of the event, rubbing of hands, smacking of lips: chewing, fiddling with objects.
o Secondary generalised: partial seizures begin in one part of the brain and spread to the whole brain and tonic clonic seizures occur.
What are the generalised seizures?
o Absence: staring and blinking, daydreaming, mainly affects children and lose awareness for 5-20 seconds
o Myoclonic: brief muscle jerking or one or both arms and legs. Last a fraction of a second and remains conscious.
o Tonic: all muscles of the body contract causing falling but with convulsions. Lasts <20 seconds
o Tonic clonic: most common seizures with two stages: whole body convulse/twitch. Lasts 1-2 minutes with possible incontinence
o Atonic: all muscle tone lost very briefly; fall limpy to the ground. Head injury likely to occur. No confusion likely to get up after
What are the precipitating factors for seizures?
- Sleep deprivation/physical exhaustion
- Emotional stress
- Increased body temperature
- Environmental factors: flashing lights
- Menstruation
- Metabolic disturbances
- Excessive alcohol/drug misuse
- Certain medication
- Non-compliance with drug therapy
What are the key investigations?
- Clear history & eyewitness accounts of seizures (Most already with
- known history of epilepsy)
- Blood pressure measurement +obs, urinalysis
- Blood tests
o Haematology (FBC, platelets, coagulation screen, blood fil, thrombophilia screen)
o Biochemistry (U&Es, urate, glucose, serum calcium and sodium, LFTs)
o Toxicology screening - Computerised tomography scan (CT scan)
o Look for evidence of cerebral structural damage - Magnetic resonance imaging (MRI)
o More detailed view of brain structural changes - Electroencephalogram (EEG)
o Classifies seizure type by identifying origin of abnormal electrical discharge
o Gives you the diagnosis- tells you where the seizure is - Telemetry
o Uses video & EEG in order to observe & identify seizure type
What are the managements of epilepsy?
- Aims to identify cause of seizures & prevent recurrence (if possible)
- Usually requires anti-epileptic drugs (AED) which may be lifelong; complete control gained in 70%+ of cases
- Majority treated with monotherapy; 5-10% require polytherapy; a few will require surgery
- Aim of therapy is to use lowest possible dose of AEDs in order to control seizures, as all drugs have side effects
- Dosage needs to be adjusted during weight gain (pregnancy) and weight loss (illness)
What do you do when someone is having an epileptic fit?
- A –Assess the situation – are they in danger of injuring themselves? Remove any nearby objects that could cause injury
- C -Cushion their head (with a jumper, for example) to protect them from head injury
- T – Time, Check the time – if the seizure lasts longer than five minutes you should call an ambulance
- I – Identity, Look for a medical bracelet or ID card – it may give you information about the person’s seizures and what to do
- O –Over, Once the seizure is over, put them on their side (in the recovery position). Stay with them and reassure them as they come round
- N – Never restrain the person, put something in their mouth or try to give them food or drink
What are anti-epileptic drugs?
- These are anticonvulsant drugs
- Usually they act by suppressing the hyperexcitability of neurons in the cerebral cortex
- Some act by enhancing the activity of the inhibitory neurotransmitter, GABA (gamma aminobutyric acid)
- Common side-effects of AEDs (dose-related)
- Drowsiness, irritability, vertigo, double vision, poor memory, loss of concentration, weight gain/loss
- Most people with epilepsy (70-85%) can control recurrent seizures adequately with these drugs
Enzyme-inducing dugs
- Drugs that cause the liver to increase its production of certain enzymes
o Can result in increased rate of breakdown of drugs
o Can reduce effectiveness of oral contraceptive pill
Examples: - Carbamazepine (“Tegretol”)
- Phenytoin (“Epanutin”)
- Topiramate (“Topamax”)
- Primidone (“Mysoline”)
- Oxcarbazepine (“Trileptal”)
- Phenobarbitone
Non-enzyme inducing drugs
- These drugs do not have the same effect on liver enzymes and are not thought to interfere with effectiveness of oral contraceptive pill Examples: - Sodium valproate (“Epilim”) - Gabapentin (“Neurontin”) - Clonazepam (“Rivotril”) - Vigabatrin (“Sabril”) - Zonisamide (“Zonegran”)
What are the complications of epilepsy?
- Status epilepticus – repeated seizures without any recovery of consciousness
- Trauma – occurring at the time of the convulsion i.e. tongue biting, head trauma, hot water burns
- Cardio-respiratory failure – arising from status epilepticus where treatment was delayed
- Sudden Adult Death – Phenomenon whereby patient dies suddenly and no toxicological or anatomic cause of death is apparent
o Sudden unexpected death in epilepsy (SUDEP)
o High seizure frequency
o Polytherapy to control condition (> 3 drugs)
o Early-onset epilepsy
o Poor compliance/concordance with medication regime
What is the pre-conception issues and care?
- All women should be offered preconception counselling
- Pregnancy deferred until seizure control is optimal
- Current medication should be reviewed and changed if necessary
- AEDs: Increased risk of folate deficiency and therefore neural tube defects= 5mg folic acid before and up to 12/40
- Women who have been seizure free for a minimum of 5yrs may consider withdrawing AEDs
- AEDs should be used at the lowest number and dose of drugs possible as polytherapy = ↑Major Congenital Malformations
