25. Weakness Flashcards

Question

if a non-contrast CT shows ishcameic stroke/rules out haemorrhage, what other scans might you get?

Answer 1

CT angiography particularly if thrombectomy is being considered MR angiography CT perfusion scan or diffusion weighted MRI if looking for salvagable brain tissue

Answer 2

OCP is a risk factor Migraine is a risk factor AF is a risk factor Antipsychotics is risk factor Polycythaemia vera (raised RBC - hyperviscosity)

Answer 3

1. Aspirin 300mg orally or rectally should be given as soon as possible if a hemorrhagic stroke has been excluded. Continue for 2 weeks. + Thrombolysis with alteplase if <4.5 hours since symptom onset + Thrombectomy if <6 hours (together with Thrombolysis with alteplase if <4.5 hours) and confirmed occlusion of the proximal anterior circulation demonstrated by CTA or MRA

Answer 4

1. aspirin 300mg orally or rectally should be given as soon as possible if a hemorrhagic stroke has been excluded. Continue for 2 weeks. CT perfusion or diffusion-weighted MRI + thrombectomy if between 6 hours and 24 hours (including wake-up strokes) if there is the potential to salvage brain tissue, + consider if proximal posterior circulation

Answer 5

DVT risk management: pressure stockings, IPCDs, not dalteparin as it could cause hemorrhagic transformation SALT referral for swallow screen - make nil by mouth in the meantime Disability is most commonly measured using the Barthel index (BI) ECG for ?AF If AF, 'anticoagulants should not be started until brain imaging has excluded haemorrhage, and usually not until 14 days have passed from the onset of an ischaemic stroke'

Answer 6

24hr after thrombolysis do another CT to check you haven't caused haemorrhagic transformation Young person more likely to get raised ICP as their brain isn't atrophied so no space t swell - be alert for decrease in GCS

Answer 7

- Previous intracranial haemorrhage - Seizure at onset of stroke - Intracranial neoplasm - Suspected subarachnoid haemorrhage - Stroke or traumatic brain injury in preceding 3 months - Lumbar puncture in preceding 7 days - Gastrointestinal haemorrhage in preceding 3 weeks - Active bleeding - Pregnancy - Oesophageal varices - Uncontrolled hypertension >200/120mmHg

Answer 8

1. Clopidogrel 2. Aspirin plus modified-release (MR) dipyridamole 3. MR dipyridamole if the cholesterol is > 3.5 mmol/l patients should be commenced on a statin. Atorvostatin 80mg. Many physicians will delay treatment until after at least 48 hours due to the risk of haemorrhagic transformation If AF, 'anticoagulants should not be started until brain imaging has excluded haemorrhage, and usually not until 14 days have passed from the onset of an ischaemic stroke'

Answer 9

consider carotid artery endarterectomy: - if stroke/tia in carotid territory (eyes, ACA, MCA) and they are not severely disabled - should only be considered if carotid stenosis > 70% according ECST** criteria or > 50% according to NASCET*** criteria - Don’t operate on completely blocked as it is sealed so doesn’t embolize and cause strokes Don’t operate on a asymptomatic carotid

Answer 10

strokes involving the anterior cerebral artery / middle cerebral artery they cause: - Unilateral hemiparesis +/- hemisensory loss of 2 of: face, arm and leg - Homonymous hemianopia - High cognitive dysfunction eg dysphasia Total anterior circulation - all 3 of above criteria Partial anterior circulation - 2 of above criteria

Answer 11

Anterior cerebral artery - contralateral hemiparesis + sensory loss (LL worse than UL) Middle cerebral artery - contralateral hemiparesis + sensory loss (UL worse than LL)

Answer 12

Involve the vertebrobasilar (posterior cerebral, cerbellar arteries, basilar arteries) arteries and presents with one of: - Cerebellar or brainstem syndromes - Loss of consciousness - Isolated homonymous hemianopia

Answer 13

- Posterior cerebral artery - Weber's syndrome (branch of PCA→ midbrain) - Anterior inferior cerebellar artery AICA (lateral pontine syndrome) - Posterior inferior cerebellar artery PICA (lateral medullary/wallenberg) - Basilar artery - Lacunar infarct

Answer 14

contralateral homonymous hemianopia with macular sparing with visual agnosia

Answer 15

ipsilateral CN 3 palsy, contralateral weakness of upper and lower extremity

Answer 16

(lateral pontine syndrome) - ipsilateral facial paralysis, deafness, vertigo and vomiting

Answer 17

(lateral medullary/wallenberg) - ipsilateral facial pain and temperature loss, contralateral limb/torso pain and temp loss, ataxia, nystagmus

Answer 18

locked in syndrome quadriplegia

Answer 19

1 of: unilateral weakness of ⅔ of face,arm,leg(+/- sensory defecit), pure sensory stroke, ataxic hemiparesis. Often causes by HTN.

Answer 20

involves the perforating arteries around the internal capsule, thalamus and basal ganglia.

Answer 21

immediate antithrombotic therapy - Give aspirin 300mg unless: --> pt has a blleeding disorder or taking anticoag (need CT to exclude ahemorrhage) --> pt already taking low dose aspirin (contnue current dose) --> aspirin contarindicated (discuss with specialist urgently) Specialist review - admit if crescenddo TIA or ?carotid stenosis or ?cardioembolic - within 24 hours if happene din past 7 days - within 1 week if symptoms were more than a week ago

Answer 22

Advise the person not to drive until they have been seen by a specialist

Answer 23

Similar to ischaemic stroke or reduced consciousness Nausea Vomiting Headache Reduced GCS

Answer 24

Metastasis Vascular malformations (AVLs) Sinus venous thrombosis Hypertension (most common)

Answer 25

stop anticoagulants and antithombotics. consider reversal neurosurgical consult

Answer 26

Hypoglycaemia Todd’s paresis Migraine Bell’s palsy

Answer 27

Bell's palsy may be defined as an acute, unilateral, idiopathic, facial nerve paralysis. The aetiology is unknown although the role of the herpes simplex virus has been investigated previously. The peak incidence is 20-40 years and the condition is more common in pregnant women.

Answer 28

STROKE bells palsy has 5 branches so hand on face = it all so not forehead sparing lower motor neuron facial nerve palsy - forehead affected in contrast, an upper motor neuron lesion 'spares' the upper face patients may also notice post-auricular pain (may precede paralysis), altered taste, dry eyes, hyperacusis

Answer 29

1. Oral prednisolone within 72 hours of onset of Bell's palsy - seek specialist advice about use of antivirals

Answer 30

if the paralysis shows no sign of improvement after 3 weeks, refer urgently to ENT a referral to plastic surgery may be appropriate for patients with more long-standing weakness e.g. several months

Answer 31

most people with Bell's palsy make a full recovery within 3-4 months if untreated around 15% of patients have permanent moderate to severe weakness

Answer 32

Myasthenia gravis is an autoimmune disorder resulting in insufficient functioning acetylcholine receptors. Antibodies to acetylcholine receptors are seen in 85-90% of cases*. Myasthenia is more common in women (2:1)

Answer 33

The key feature is muscle fatigability - muscles become progressively weaker during periods of activity and slowly improve after periods of rest: extraocular muscle weakness: diplopia proximal muscle weakness: face, neck, limb girdle ptosis dysphagia

Answer 34

extraocular muscle weakness: diplopia proximal muscle weakness: face, neck, limb girdle ptosis dysphagia

Answer 35

Beta-blockers — should be avoided if possible in patients with myasthenia gravis lithium phenytoin antibiotics: gentamicin, macrolides, quinolones, tetracyclines penicillamine quinidine, procainamide

Answer 36

AChR antibodies (acetylcholine receptor antibody) single fibre EMG (stimualtion of single fibres) high sensitivity (92-100%) CT thorax to exclude thymoma

Answer 37

1. long-acting acetylcholinesterase inhibitors pyridostigmine is first-line (too tired to get to top of pyramid) + immunosuppression such as prednisolone + thymectomy

Answer 38

- plasmapheresis - intravenous immunoglobulins

Answer 39

suxamethonium (muscle relaxant) normal doses won't work Suxamethonium is a depolarising NMBD - it acts by binding to and activating the receptor, at first causing muscle contraction, then paralysis. Due to a decreased number of available receptors, MG patients are typically resistant to depolarising NMBDs and may require significantly higher doses.

Answer 40

statins - CK will be raised steroids - CK raised if acute, not raised if chronic

Answer 41

Rhabdomyolysis is caused by skeletal muscle breakdown. This causes the release of intracellular contents such as myoglobin and potassium into the blood stream. Excess myoglobin can precipitate in the glomerulus causing renal obstruction, direct nephrotoxicity and acute kidney injury.

Answer 42

dark urine, generalised weakness and myalgia.

Answer 43

acute kidney injury with disproportionately raised creatinine elevated creatine kinase (CK) myoglobinuria hypocalcaemia (myoglobin binds calcium) elevated phosphate (released from myocytes) hyperkalaemia (may develop before renal failure) metabolic acidosis

Answer 44

seizure collapse/coma (e.g. elderly patients collapses at home, found 8 hours later) Ischaemia: embolism, surgery ecstasy crush injury McArdle's syndrome drugs: statins (especially if co-prescribed with clarithromycin)

Answer 45

A creatine kinase >5x the normal range is typically diagnostic.

Answer 46

IV fluids to maintain good urine output Correction of electrolyte disturbances urinary alkalinization is sometimes used

Answer 47

Hyperkalaemia (liberated from the damaged muscle) Hyperphosphatemia (liberated from the damaged muscle) Hyperuricaemia (liberated from damaged muscle) Hypocalcaemia (calcium is taken into the damaged muscle by several mechanisms).

Answer 48

cushings hypoadrenalism

Answer 49

umbrella term for genetic conditions that cause gradual weakening and wasting of muscles.

Answer 50

Children with proximal muscle weakness use a specific technique to stand up from a lying position. This is called Gower’s sign. To stand up, they get onto their hands and knees, then push their hips up and backwards like the “downward dog” yoga pose. They then shift their weight backwards and transfer their hands to their knees. Whilst keeping their legs mostly straight they walk their hands up their legs to get their upper body erect. This is because the muscles around the pelvis are not strong enough to get their upper body erect without the help of their arms.

Answer 51

Supportive Management is aimed at allowing the person to have the highest quality of life for the longest time possible. This usually involves input from occupational therapy, physiotherapy and medical appliances (such as wheelchairs and braces) as well as surgical and medical management of complications such as spinal scoliosis and heart failure.

Answer 52

defective gene for dystrophin on the X-chromosome X-linked recessive condition

Answer 53

50% chance of being a carrier if they are female and 50% chance of having the condition if they are male.

Answer 54

Boys with Duchenne's present around 3 – 5 years with weakness in the muscles around their pelvis. The weakness tends to be progressive and eventually all muscles will be affected. They are usually wheelchair bound by the time they become a teenager.

Answer 55

The clinical course is less predictable than Duchennes. Symptoms only start to appear around 8 – 12 years. Some patients require wheelchairs in their late 20s or 30s . Others are able to walk with assistance into later adulthood. Management is similar to Duchennes.

Answer 56

the dystrophin gene is less severely affected and maintains some of its function

Answer 57

Prolonged muscle contractions This may present in exams with a patient that is unable to let go after shaking someones hand, or unable to release their grip on a doorknob after opening a door. When doing an upper limb neurological examination always shake the patients hand and observe for difficulty releasing their grip.

Answer 58

Horner's syndrome - anhydrosis determines site of lesion: head, arm, trunk = central lesion: stroke, syringomyelia 1st order just face = pre-ganglionic lesion: Pancoast's, cervical rib 2nd order absent = post-ganglionic lesion: carotid artery 3rd order imaging eye drops to determine site of lesion- apraclonidine to confirm horners followed by hydroxyamphetamine to determine site of lesion