Hemiparesis

Relevant clinical signs

• Inspection
  • Walking aids
  • Facial droop
  • Feeding tubes, nil by mouth signs (dysphagia)
  • Flexor posturing of the upper limbs, extensor of the lower limbs
• Limbs
  • Positive pronator drift on affected side
  • Increased tone, velocity-dependent
  • Reflexes
    • Brisk reflexes on the affected side
    • Positive Hoffman’s sign on the affected side
    • Extensor plantar response on the affected side
    • Ankle clonus on the affected side
  • Pyramidal weakness
    • Flexors stronger than extensors in upper limb on the affected side
    • Extensors stronger than flexors in lower limb on the affected side
    • Severe hemiparesis may affect all muscle groups equally
  • Sensation
    • Brainstem syndromes
      • Weber’s: ipsilateral III, contralateral hemiparesis
      • Millard-Gubler: ipsilateral VI, VII, contralateral hemiparesis, dorsal column loss
    • Cord syndromes
      • Brown-Séquard: ipsilateral hemiparesis and dorsal column loss, contralateral spinothalamic loss
    • May have cortical sensory loss: astereognosis, agraphesthesia rather than modality loss
• Cortical function
  • Hemineglect
  • Homonymous hemianopia
  • Gaze preference (towards the side of the lesion)
  • Expressive dysphasia
  • Anomia
  • Cortical sensory loss
  • Reduced Glasgow Coma Scale (cerebral oedema)
• Underlying cause
  • Pulse (atrial fibrillation)
  • Carotid bruit (internal carotid artery stenosis)
  • Finger prick marks, diabetic dermopathic changes (diabetes mellitus)
  • Bruising, metallic heart sounds (anticoagulation)

Differential diagnosis

• Ischaemic stroke
  • Cardioembolic
  • Internal carotid artery stenosis
  • Hypertensive disease
  • Cerebral vasculitis
• Haemorrhagic stroke
• Brain abscess
• Brain tumour
• Post-ictal (Todd’s paresis)

 Investigations

• Confirm diagnosis:
  • Computed tomography scan of the brain (established infarcts) ± CT angiography (thrombolysis)
  • Magnetic resonance imaging ± magnetic resonance angiography
• Look for an underlying cause
  • Electrocardiogram, consider Holter looking for tachyarrhythmia
  • Trans-cranial Doppler looking for stenosis
  • Doppler of the carotid arteries looking for stenosis (>70%)
  • Trans-thoracic echocardiogram looking for intramural thrombus
• Blood tests (pre-thrombolysis and before starting antiplatelets)
  • Full blood count
  • Renal function
  • Liver function
  • Coagulation screen
• Cardiovascular risk factors
  • Fasting glucose level, HbA1c
  • Lipid monitoring
• Young stroke work-up
  • ANA, dsDNA, ESR
  • Anti-phospholipid antibodies
    • Lupus anticoagulant
    • Anti-cardiolipin IgG and IgM
    • Anti-β₂ glycoprotein IgG and IgM
  • Thrombophilia screen
    • Protein C and protein S (deficiency)
    • Anti-thrombin III (deficiency)
    • Homocysteine (high)
  • Syphilis screen

Management

• Multidisciplinary team approach
• Speech therapy for swallowing, communication
• Physiotherapy and occupational therapy to preserve and maximize function
• Acute management
  • Stabilize, intubate if unable to protect airway
  • Within thrombolytic window (4½ hours of clear symptom onset)
    • No established infarct on CT brain
    • National Institutes of Health Stroke Scale > 5
    • Contraindications: recent stroke, age ≥ 80, bleeding diathesis, NIHSS ≥ 25, BP > 185/110
    • Complications: haemorrhagic conversion (BP must be < 180/105 for 24h post-thrombolysis)
  • Out of window
    • Load antiplatelet, or change from aspirin to clopidogrel if already on aspirin
    • Statin
    • Gastric protection if starting aspirin
    • If cardioembolic – anticoagulate
• Manage cardiovascular risk factors
  • Smoking cessation
  • Weight loss
  • Diabetic control
  • Hypertension control
• Consider neurosurgical referral for decompression if haemorrhagic conversion / cerebral oedema