High yield exam cram Flashcards
Name the cells that produce myelin in
A) CNS
B) PNS
CNS = oligodendrocytes
PNS = Schwann cells
Where in the brain is
A) Broca’s area
B) Wernicke’s area
Broca’s area = frontal lobe
Wernicke’s area = Posterior superior temporal lobe
What is the function of
A) Broca’s area
B) Wernicke’s area
Also describe the aphasia of each region if they become damaged
A) Broca’s = production of speech – (damage causes non-fluent aphasia with word finding difficulties)
B) Wernicke’s = processing & understanding speech – (damage causes fluent aphasia, talks nonsense
Which regions of the brain are responsible for
A) Visual processing
B) Auditory processing
A) Visual = parietal lobe
B) Auditory = Temporal lobe
where are the cell bodies of motor nerves found?
Ventral horn
where are the cell bodies of sensory nerves found?
Dorsal horn
Explain the pathway of an upper and lower motor neurone (from CNS to muscle)
brain and brainstem -> ventral horn of the spinal cord (changes from upper to lower motor neurone here) -> peripheral muscles
Describe the action of a parasympathetic neuromuscular junction
Ach ->
nicotinic receptor on postganglionic neuron ->
Ach ->
muscarinic receptor on target organ
Describe the action of a sympathetic neuromuscular junction
Ach ->
nicotinic receptor on post ganglionic neuron ->
norepinephrine ->
adrenergic receptors on target organ
Describe the findings in an upper motor neurone lesion
UPPER (everything is UP) – lesion is in brain or spinal cord (above level of ventral horn)
- Hyperreflexia
- Upgoing plantars
- Increased tone
Where is an upper motor neurone lesion?
lesion is in brain or spinal cord (above level of ventral horn)
Where is a lower motor neurone lesion?
Lesion is in peripheral nerves (below level of anterior horn)
Describe the findings in a lower motor neurone lesion
LOWER (everything is down) –
- Reduced/absent reflexes
- Down going plantars/no response
- Reduced tone
- Muscle atrophy/fasciculations
What function are the following spinal tracts responsible for
- The Corticospinal/ pyramidal tract
- The Posterior/ dorsal column
- The Lateral spinothalamic tract
Describe the neurological findings in brown squared syndrome
Ipsilateral loss of fine touch, vibration, proprioception & motor
Contralateral Loss of pain & temp
What causes brown squared syndrome?
Damage to half of the spinal cord
Which type of fibres pick up proprioception
A-alpha (myelinated)
Which type of fibres pick up ‘touch’
A-Beta (myelinated)
Which type of fibres pick up sharp pain?
Unmyelinated C fibres (small and slow)
Which type of fibres pick up dull pain?
Myelinated A-delta fibres (myelinated and fast)
What is the definition of allodynia?
pain experienced with a sensory input that does not normally cause pain
Explain the difference between chronic primary pain and chronic secondary pain and the way that they should be managed
Chronic primary pain = no underlying cause – DO NOT START PATIENTS ON PAIN MEDS (but u can start antidepressants)
Chronic secondary pain = underlying cause. Medications targeted to the underlying cause are fine
State the type of medication each of the following are:
Amitriptyline
Duloxetine
Gabapentin and pregabalin
- Amitriptyline = tricyclic antidepressant
- Duloxetine = SNRI antidepressant
- Gabapentin & Pregabalin = anticonvulsant
How is a breakthrough dose of morphine calculated?
Breakthrough dose = 1/6th of daily morphine dose
How is oral codeine/tramadol converted to oral morphine?
divide by 10
How is oral morphine dosing converted to subcutaneous morphine?
divide by 2
What is normal intracranial pressure?
7-15mm
What is Cushing’s triad?
bradycardia, hypertension and irregular breathing
How is Cerebral perfusion pressure calculated?
Cerebral perfusion pressure (CPP) = Difference between mean arterial pressure (MAP) -intracranial pressure (ICP)
What are the functions of the following structures in relation to memory:
- Hippocampus
- Cortex
- Thalamus
- Limbic system
- Hippocampus (forms memories)
- Cortex (stores memories)
- Thalamus (Searches and accesses memories)
- Limbic system (adds emotion significance to events which helps in the formation of memory)
What is meant by integrate memory loss?
inability to form new memories
What is meant by retrograde memory loss?
inability to access old memories
What are the 4 main wave patterns seen on EEG?
Beta
Alpha
Theta
Delta
Explain the appearance of each wave and when you might see it
Describe the 4 stages of sleep and what waveform is seen in each
Stage 1- dozing. High amplitude, low frequency, slow theta waves.
Stage 2- regular sleep. Sleep spindles
Stage 3- deep sleep. High amplitude, very slow (2Hz) delta waves interspersed with short episodes of faster waves. Declining spindle activity
Stage 4- Very deep sleep. Delta waves
REM- low amplitude, high frequency (similar to the awake state)
When in the sleep cycle do sleep walking, sleep talking and night terrors occur?
Stage 4 (very deep sleep)
When in the sleep cycle do dreams and nightmares occur?
REM
When in the sleep cycle does REM occur?
Once the body reaches stage 4 sleep, the body then moves back up through stage 3 and stage 2 before entering REM sleep.
lasts 5-30 mins every 90 mins
Which stage in the sleep cycle do narcoleptics fall straight into?
REM
What is meningitis?
Infection/inflammation of the meninges
What is encephalitis?
Infection/inflammation of the brain
What is myelitis?
Infection/inflammation of the spinal cord
What is the most common bacterial cause of meningitis?
Neisseria Meningititis
What is the most common viral cause of meningitis?
Enteroviruses e.g. coxsackie
In which type of infection (bacterial/viral/fungal) would you see a fibrin web in the lumbar puncture?
Fungal
What glucose measurement would you expect in the CSF of a person infected with:
A) Bacteria
B) Virus
C) Fungus
A) Bacteria = <2.2 (low)
B) Virus = normal
C) Fungus = 1.6-2.5 (low)
What is the initial empirical treatment of meningitis in babies <3m?
IV cefotaxime + amox
What is the initial empirical treatment of meningitis in those aged 3M-50Y
IV cefataxime
What is the initial empirical treatment of meningitis in those >50Y?
IV cefotaxime + Amox
What is the initial empirical treatment of meningitis in those with meningococcal meningitis?
IV benzylpenicillin or cefotaxime
What is the initial empirical treatment of meningitis in those with meningitis caused by listeria?
IV amox + gent
What is the most common cause of encephalitis?
Herpes simplex
What are the 2 antibodies associated with autoimmune encephalitis?
Anti-VGKC and Anti-NMDA
What is the most common cause of brain abscess?
Strep
What are the 3 steps to manage rabies immediately post-exposure?
Wash wound
Give active rabies immunization
Give human rabies immunoglobulin (passive immunisation) if high risk
What is the preventative treatment for tetanus?
Inactivated tetanus vaccine
What is the treatment for tetanus after an exposure?
Penicillin
Immunoglobulin for high risk wounds/patients
What is the treatment for botulism?
Anti-toxin (A,B,E)
Penicillin / Metronidazole (prolonged treatment)
Radical wound debridement
What kind of organism causes Creutzfeldt-Jakob?
Prion
How is Creutzfeldt-Jakob diagnosed?
MRI, EEG, CSF
What is the treatment for Creutzfeldt-Jakob?
There is no treatment
What are the three main features of Wernicke’s encephalopathy?
nystagmus
Opthalmaplegia
Ataxia
What are the features of Korsakoff’s encephalopathy?
Wernicke’s (nystagmus, opthalmaplegia, ataxia) +
Amnesia
Confabulation
What is confabulation?
gaps in memory are unconsciously filled with fabricated, misinterpreted, or distorted information
Describe the physical manifestations of a tonic clonic seizure
Rigid and shaking
Describe the physical manifestations of a tonic seizure
Stiffening
Describe the physical manifestations of an atonic seizure
Drop attacks
Describe the physical manifestations of a myoclonic seizure
Jump or jolt
Describe the physical manifestations of an absent seizure
Staring into space
Describe the physical manifestations of a partial/focal seizure
Rising feeling in stomach
Funny taste/ smell
Deja vu
Lip smacking
Repetitive picking at clothing
Where in the brain does a focal/partial seizure occur?
Temporal lobe
Describe the physical manifestations of an infantile spasm
Cyclical, repetitive full body spasming and relaxing
What is another name for infantile spasms?
West syndrome
Is the prognosis of west syndrome good or bad?
Bad
What are the treatments for tonic clonic, tonic and atonic seizures?
Men/women not able to get pregnant: Sodium valproate
Women able to get pregnant: Lamotrigine
What is the treatment for myoclonic seizures?
Men/women not able to get pregnant: Sodium valproate
Women able to get pregnant: Levetiracetam
What is the treatment for absent seizures?
Ethosuximide
What is the treatment for partial/ focal seizures?
Lamotragine
What is the treatment for west syndrome?
ACTH and Vibagatrin
What is ‘status epileptics’?
seizure lasting >5 minutes or repeated seizures without regaining consciousness in between
What are the rules regarding driving after a first seizure with NORMAL investigations
Group 1 vehicles after 6 months
Group 2 (HGV) vehicles after 5 years
What are the rules regarding driving if you have a diagnosis of epilepsy?
Have been seizure free for one year
Have an established pattern of seizures only during sleep for at least 1 year
If awake seizures as well as sleep seizures, established pattern of only sleep seizures for three years
Should not drive during medication withdrawal and for 6 months thereafter
What is the definition of a primary headache vs a secondary headache?
Primary headache = no underlying medical cause. Caused by sensitisation of normal pain pathways
Secondary headache = underlying medical cause (e.g. meningitis)
What causes a postural headache?
Low pressure (e.g. CSF leak)
Describe the management of a tension headache (acute & preventative)
Acute: Paracetamol & NSAIDs
Preventative: Tricyclic antidepressants (amitriptyline)
Describe the management of a cluster headache (acute & preventative)
Acute: Nasal triptans, high flow oxygen,
Preventative: Verapamil
Describe the management of a migraine (acute & preventative)
Acute: NSAIDs, paracetamol, Triptans, anti-emetics
Preventative: trigger management, propranolol
Describe the management of a medication overuse headache
Withdraw medications
Describe the management of a sub arachnoid haemorrhage (diagnosis and management)
Diagnosis: CT Head as soon as possible
Lumbar Puncture > 12 hours after headache onset
Management: Clipping/coiling of aneurysms
Nimodipine (Ca2+ channel blocker for vasospasm)
Describe the management of raised ICP
Bed rest, fluids, analgesia, caffeine
Epidural blood patch (stiffens the meninges and helps symptoms)
Describe the management of a hormonal headache
Triptans and NSAIDs
Describe the management of giant cell arteritis (diagnosis and treatment)
Diagnosis: ESR & biopsy
Management: High dose prednisolone