Neurological Conditions Flashcards
What is a stroke
A cerebrovascular event that is caused by abnormal perfusion of cerebral tissue.
A common medical emergency that requires urgent recognition and treatment.
A clinical syndrome characterised by sudden onset of rapidly developing focal or global neurological disturbance, which lasts more than 24 hours or leads to death.
What are the two types of stroke
Haemorrhagic
Ischaemic
What is an ischaemic stroke
Are due to occlusion of blood vessels that supply the brain parenchyma leading to infarction (tissue necrosis secondary to ischaemia).
What is a haemorrhagic stroke
Haemorrhagic strokes are the result of bleeding within the brain parenchyma, ventricular system or subarachnoid space.
What is the Bamford/Oxford classification
Used to sub classify ischaemic strokes
It differentiates ischaemic strokes based on the presenting features which correlated with the cerebral territory affected
Total anterior circulation stroke (TACS)
Partial anterior circulation stroke (PACS)
Lacunar stroke (LACS)
Posterior circulation stroke (POCS)
How common are strokes
~110,000 per year in England
Mortality from first ever stroke is 11%
What is the cause of ischaemic strokes
- Caused by occlusion of cerebral blood vessels
- Most common accounting for 85% of cases
- Can result from a thrombus within a vessel, embolus arising from a distant site, or rarely, a dissection.
What is the cause of hemorrhagic strokes
- Result from bleeding
- Accounts for 15% of cases
- Most commonly due to hypertension
- Other causes include vascular malformations, brain tumour, vasculitis, bleeding disorders
- Trauma is another major cause but usually classified as part of traumatic brain injuries
What are the risk factors for strokes
Smoking Diabetes mellitus Hypertension Hypercholesterolaemia Obesity AF Carotid artery disease Age Thrombophilic disorders Sickle cell disease
How do each type of stroke present
A stroke presents with sudden, focal neurological deficit that reflects the area of brain devoid of blood flow.
Haemorrhagic:
- More likely to present with global featurese
- Headache
- Altered mental state
- Nausea/vomiting
- Hypertension
- Seizures
- Focal neurological deficits
Anterior ischaemic stroke:
- TACS, PACS, LACS
- Develop a constellation of features dependent on the extent and location of the infarct
- Unilateral weakness and/or sensory deficit to face, arms or legs
- Homonymous hemianopia
- Higher cerebral dysfunction: dysphasia, visuospatial dysfunction
- Classically, isolated infarction of the anterior cerebral artery leads to contralateral leg wekness only
Posterior ischaemic stroke:
- Posterior circulation is composed of the vertebrobasilar artery system
- This supplies the brainstem, cerebellum and occipital cortex
- Therefore, posterior strokes can affect balance, vision and cranial nerves
- Dizziness
- Diplopia
- Dysarthria and dysphagia
- Ataxia
- Visual field defects
- brainstem syndromes
What are the differentials for stroke
Numerous conditions present similarly to stroke - aka ‘stroke mimics’
Toxic/metabolic:
- hypoglycaemia
- drug/alcohol consumption
Neurological:
- seizure
- migraine
- Bell’s palsy
Space occupying lesion:
- tumour
- haematoma
Infection:
- meningitis/ encephalitis
- systemic infection with ‘decompensation’ of old stroke
Syncope:
- extremely uncommon presentation of TIA
- consider causes of syncope
Non-organic:
-functional neurological disorders (FND)
How is a suspected stroke investigated
Any patient with suspected stroke, refer to stroke unit urgently
Initally clinically diagnosed based on history and examination
Fast test used in community to screen patients for urgent transfer
In hospital, NIHSS score is used in correlation with urgent cross-sectional imaging (CT head ± CT angiography)
Clinical assessment:
- Onset and duration of symptoms
- Associated symptoms
- Neurological deficit
- Cardiovascular risk factors
- Co-morbidities
- Anticoagulation history
- Contraindications to thrombolysis or thrombectomy
FAST test (Face Arm Speach Time)
- Positive test if:
- New facial weakness
- New arm weakness
- New speech difficulty
CT head is the key investigation in patients presenting with a suspected stroke
Bedside:
- Observations
- Blood glucose
- ECG (AF)
Bloods:
- FBC
- UandEs
- Bone profile
- LFT
- ESR
- Coagulation
- Lipid profile
- HbA1c
Imaging:
- CT head
- CT angiography
- MRI head
Special tests:
- Echocardiography
- Carotid dopplers
- 24 hour tape
- Young stroke screen
What are important discussions to have with a stroke patient
Advise not to drive and to inform the DVLA
How is each type of stroke treated
“Acute management:
Determine type of stroke on the initial CT
Haemorrhagic stroke:
Management depends on the extent of the bleed and suitability for neurosurgical interventions
In small bleeds, no need for surgery
Surgical intervention may be required for larger bleeds with significant neurological deterioration
Includes use of decompressive hemicraniectomy or suboccipital craniotomy for posterior fossa bleeds
Ischaemic stroke:
If the CT head does not reveal any signs of intracerebral bleeding then the patient is managed as an ishcemic stroke
A initial decision is made about suitability of thrombolysis based on stroke severity, contraindications and timeframe
Thrombolysis: synthetic tissue plasminogen activator (eg Alteplase)- clotbusting drug
Contraindications: (neurosurgery last 3 months, active internal bleeding etc)
NIH stroke scale: consider if score between 5 and 26
Timeframe: within 4.5 hours (thrombolysis window) Limited benefit beyon this time with increased bleeding risk
If thrombolysis is not appropriate, start immediately on 300mg of aspirin for two weeks, after two weeks, conversion to secondary prophylaxis with 75mg clopidogrel is indicated unless anti-coagulation is appropriate because of aetiology
If thrombolysis was given, aspirin is usually started 24-48 hours following treatment
Thrombectomy:
Removal of thrombus from a vessel
Ongoing management: Admission to a hyperacute stroke unit for ongoing monitoring is essential BP control Blood glucose control Anti-lipid therapy Anti-platelet/ anti-coagulation Carotid artery assessment Swallow and nutrition assessment Rehabilitation Palliative care
What are potential complications following a stroke
Early: Haemorrhagic transformation of ischaemic stroke Cerebral oedema Seizures Infection (e.g. aspiration pneumonia) Cardiac arrhythmias Venous thromboembolism Death
Late: Mobility & sensory issues Bladder & bowel dysfunction Pain Fatigue Cognitive problems Visual problems Emotional and psychological issues Issues with swallowing, hydration and nutrition
What is the prognosis of stroke
4th leading cause of death in Uk
1/7 patient with acute stroke die in hospital
~40& will have ongoing difficulties with basic activities of daily living 6 months after their stroke
What is a sub-arachnoid haemorrhage
Bleeding into the subarachnoid space, where the cerebrospinal fluid is located, between the pia mater and the arachnoid membrane
Who is most affected by sub-arachnoid haemorrhage
Black patients
Female
Age 45 to 70
What causes a sub-arachnoid haemorrhage
Usually the result of a ruptured cerebral aneurysm
What are the risk factors for a sub-arachnoid haemorrhage
Hypertension Smoking Excessive alcohol consumption Cocaine use Family history Sickle cell anaemia Marfan syndrome Ehlers Danlos syndrome Neurofibromatosis
How does a sub-arachnoid haemorrhage present
Sudden onset occipital headache (AKA thunderclap headache) that occurs during strenuous activity such as weight lifting or sex
Described like being hit really hard on back of the head
Neck stiffness
Photophobia
Neurological symptoms such as visual changes, speech changes, weakness, seizures and loss of consciousness
How is a sub-arachnoid haemorrhage investigated
Immediate CT head
Blood will cause hyperattenuation in the subarachnoid space
Normal CT does not always exclude diagnosis
Lumbar puncture
Collect a sample of CSF if CT head is negative
Raised red cell count
Xanthrochromia (yellow coloured CSF caused by bilirubin
Angiography
CT or MRI can be used once a subarachnoid haemorrhage is confirmed to locate the source of the bleed
How is a sub-arachnoid haemorrhage treated
Managed by specialist neurosurgical unit
Those with reduced consciousness may require intubation and ventilation
Supportive care with nursing, nutrition and physiotherapy and occupational helath is needed throughout
Surgical intervention may be used to treat aneurysms, with the aim to repair the vessel and prevent further bleeds
Can be done through coiling, inserting a catheter into the arterial system, placing platinum coils in the aneurysm and sealing it off fromt he artery
An alternative is clipping, which involves cranial surgery and putting a clip on the aneurysm to seal it
Nimodipine is a calcium channel blocker that is used to prevent vasospasm- a common complication that can result in brain ischaemia following an SAH
LP or insertion of a shunt may be needed to treat hydrocephalus
Anti-eleptics can be used to treat seizures
What is the prognosis of a sub-arachnoid haemorrhage
Very high mortality and morbidity
What is peripheral neuropathy
Damage or disease affecting the peripheral nerves - mononeuropathy or polyneuropathy or mononeuritis multiplex (several separate mononeuropathies)
Can be acute or chronic
What causes peripheral neuropathy
Diabetes is the most common cause
Causes of Peripheral Neuropathy: A-lcohol and autoimmune diseases B-12 deficiency C-ancer and chronic kidney disease D-iabetes and drugs (eg isoniazid, amiodarone and cisplatin) E-very vasculitis
How does peripheral neuropathy present
Clove and stocking distribution is the classic sign of peripheral neuropathy
Sensory neuropathy - Diabetes, leprosy Negative symptoms: -Numbness/ pins and needles (extreme leads to loss of ability to feel pain) -Tremor -Gait abnormality -Loss of temperature change detection -Loss of coordination leading to loss of joint position sense -Loss of ankle/knee jerks Positive symptoms: -Tingling -Pain - burning or shooting pain (can be severe) -Itching -Crawling -Pins and needles
Motor neuropathy - Guillain-Barre syndrome, Charcot-Marie-Tooth syndrome Negative symptoms: -Weakness - distal muscles of hands/feet (ie foot/wrist drop) -Tiredness -Heaviness -Gait abnormalities -Reduced reflexes -Respiratory difficulty -Muscle wasting -Muscle paralysis Positive symptoms: -Cramps/myalgia -Tremor -Fasciculations -Muscle twitching
Diabetic/Polyneuropathy - autonomic neuropathy
- Dizziness and fainting (because of lack of blood pressure control, leading to low blood pressure)
- Problems with sweating - reduced ability to sweat
- Inability to tolerate heat
- Loss of control over your bladder function - incontinence of urine
- Dysphagia, bloating, constipation or diarrhoea
- Inability to achieve an erection (impotence)
- Postural hypotension
- Abnormal pupillary dilation/ contriction
- Horner’s syndrome - miosis, anhidrosis, ptosis
How is suspected peripheral neuropathy diagnosed
Diagnosis made mainly from detailed history and neuro examination
Blood tests: FBC, ESR, glucose, HbA1C, U and Es, LFT, TFT, B12, folate
Urine: glucose/protein
Genetic tests
Lead levels
Immunology: antibodies (eg intrinsic factor and gastric parietal cell antibody for Pernicious anaemia)
Nerve conduction studies
Electromyography
Nerve biopsy
Skin biopsy
MRI
LP (assesses possibiltiy of Guillain-Barre)
How is peripheral neuropathy treated
Treatment depends on cause
Physio/ occupational therapy/ Podiatrist:
- Walking aids
- Wheelchair
- Foot care
Pain management:
- Strategies to cope with pain - referral to pain management services
- Pharmacological treatment of neuropathic pain:
- Amitriptyline
- Nortriptyline
- Gabapentin
- Pregabalin
Treat the cause (eg diabetes or B12 deficiency)
Steroids
Reduced alcohol/carbs intake
For most types of neuropathy, no treatemnt is available that can cure or modify the disease. inthese cases, treatments are available for the symptoms of the disease especially pain.
- Analgesics
- Antidepressants
- Capsaisin gel
- Splints
- Surgery (decompression) - chronic symptoms, neurodeficit, Wallerian degeneration
What are potential complications of peripheral neuropathy
Depression
Permanent nerve damage
Social isolation/ breakdown of relationships due to impact of chronic pain
What is the prognosis for peripheral neuropathy
High mortality and morbidity rate (especially in DM)
Permanent joint destruction and nerve damage
Disability, social isolation, loss of independence
What is epilepsy
Epilepsy is an umbrella term for a condition where there is a tendancy to have seizures
Seizures are transient episodes of abnormal electrical activity in the brain
There are many types of seizure
A diagnosis of epilepsy is made by a specialist based on the characteristics of the seizure episodes
What are the types of epilepsy
Generalised tonic clonic seizures Focal seizures Absence seizures Atonic seizures Myclonic seizures Infantile spasms
What are the features of generalised tonic clonic seizures
Episodes of:
-Loss of consciousness
-Tonic (muscle tensing)
-Clonic (muscle jerking)
Typically the tonic phase comes before the clonic phase
May be associated tongue biting, incontinence, groaning and irregular breathing
After the seizure there is a prolonged post-ictal period where the person is confused, drowsy and irritable or depressed
