--- module: 030-02 language: en chapter: 30 title: "Stroke, Seizure, Neuropathy, Neurodegeneration, and Raised Intracranial Pressure" module_title: "Time-critical neurology, localisation, and longitudinal decline" source_sha256: 866705f0a9f0a0331718f0c38b2897aabb20d2d6ea534ad81371b994cfdd6793 --- # Time-critical neurology, localisation, and decline ## Where, what process, how fast ### Sudden maximal: vascular, haemorrhage, seizure, trauma ### Hours to days: inflammation, infection, metabolic, mass ### Weeks to months: tumour, immune, compression, degeneration ### Precise timeline from last known normal ## Acute focal deficit treated as stroke ### Reperfusion benefit decays with time ### Posterior: diplopia, dysphagia, truncal ataxia #### Low screening score does not mean benign ### Mimics: hypoglycaemia, postictal weakness, aura #### Uncertainty should accelerate imaging ## Ischaemic physiology and selection ### Arterial occlusion plus collateral failure ### Core: energy failure, cytotoxic oedema, cell death ### Penumbra: electrical failure before membrane loss #### Hypotension, hypoxaemia, fever recruit it to core ### Recanalisation, collaterals can outlast clock windows ### Selection integrates time, imaging, bleeding risk ## Imaging and reperfusion ### Non-contrast computed tomography: haemorrhage, mass #### May be normal early in ischaemia ### Angiography: large-vessel occlusion, dissection ### Thrombolysis after excluding haemorrhage ### Thrombectomy removes selected thrombi ### Complementary rather than competing ### Do not await full certainty once eligible ## Care after reperfusion decisions ### Swallow screen before oral intake #### Silent aspiration is common ### Secondary prevention follows mechanism #### Antiplatelet for most non-cardioembolic disease #### Anticoagulation for appropriate atrial fibrillation ### Handover: times, last antithrombotic dose, imaging ### Improvement may be transient attack or recanalisation ### Unknown mechanism: rhythm and vessel tests by hypothesis ## Haemorrhage ### Intracerebral haemorrhage may enlarge early ### Deep bleeds: hypertensive small-vessel damage ### Lobar bleed in older adult: amyloid angiopathy ### Cerebellar bleed compresses brainstem, blocks CSF flow #### May need urgent evacuation ### Subarachnoid: maximal within seconds or minutes ### Early aneurysm securing limits rebleeding ### Nimodipine against delayed cerebral ischaemia ## Seizure reconstruction and status ### Reconstruct the event before labelling ### Aura reveals focal onset ### Tongue injury, postictal confusion: support, not required ### Incontinence and post-syncope jerks not specific ### Status: failure of seizure termination #### Adequate benzodiazepine dose at five minutes #### Then longer-acting drug and search for cause ### Unresponsiveness after motor arrest: EEG ### First seizure: provoked versus unprovoked #### Trigger does not exclude structural lesion ## Raised intracranial pressure ### Pressure deceptively normal while reserve fades #### Then steep rise, tissue shift, herniation ### Late: anisocoria, posturing, irregular breathing ### Hypotension lowers perfusion from both sides ### Head up, neck neutral, avoid hypotonic fluid ### Hypertonic saline or mannitol: osmotic gradient #### Volume, sodium, renal, haemodynamic costs ### Brief hyperventilation constricts cerebral vessels #### Prolonged use risks ischaemia ### Defer lumbar puncture if a gradient could shift tissue ## Localising weakness and Guillain-Barre ### Upper motor neuron: tone up, brisk reflexes ### Lower motor neuron: wasting, fasciculation ### Junction: fluctuating, fatigable, sensation spared ### Normal conduction does not exclude small fibre ### Guillain-Barre: neurological, autonomic emergency #### Limb strength underestimates respiratory decline #### Serial vital capacity, cough, swallowing #### Intubate before carbon dioxide rises ### Dysautonomia makes vasoactive drugs hazardous ### Immunoglobulin or plasma exchange, not combined ## Neurodegeneration and longitudinal care ### Diagnose by first, dominant failing network ### Lewy bodies: fluctuation, hallucinations, sleep #### Marked antipsychotic sensitivity ### Frontotemporal: disinhibition, apathy, empathy loss ### Parkinson: bradykinesia plus rigidity or tremor ### Motor neuron: upper and lower signs, no sensory #### Respiratory failure without limb decline ### Repeat matched measures over time ### Stepwise decline: seek infection, drugs, vascular ### Discuss wishes while still expressible