--- module: 030-01 language: en chapter: 30 title: "Stroke, Seizure, Neuropathy, Neurodegeneration, and Raised Intracranial Pressure" module_title: "Foundations" source_sha256: 3b9fcd11b42052280346c36ee5f7e7f58b94926d10a22074c9b528e0aead917f --- # Stroke, seizure, neuropathy, neurodegeneration, pressure ## Orientation by anatomy, mechanism, time ### Sudden focal deficit: vascular until proven otherwise ### Episodic stereotyped: seizure or transient disturbance ### Progressive: degeneration, tumour, inflammation, compression ### Localise and stabilise together #### Definitive treatment depends on minutes ## Cerebral ischaemia ### Needs continuous oxygen and glucose, stores little ### Occlusion: irreversible core, hypoperfused penumbra #### Penumbra may recover if flow returns ### Glutamate, calcium, radicals, mitochondria expand injury ### Collaterals, site, pressure, glucose, time decide survival ### Transient ischaemic attack: no established infarction #### Early stroke risk can be high ### Anterior: contralateral weakness and sensory loss #### Dominant: aphasia; non-dominant: neglect ### Posterior: diplopia, dysarthria, ataxia, crossed signs ### Isolated dizziness usually not stroke #### Severe persistent vestibular syndrome, central signs ## Acute stroke treatment ### Record last known well, anticoagulants, baseline ### Non-contrast computed tomography: haemorrhage, mimics #### Normal early scan does not exclude ischaemia ### Vascular imaging finds treatable occlusion ### Diffusion imaging sensitive but must not delay treatment ### Intravenous thrombolysis within validated window ### Thrombectomy for selected large-vessel occlusion #### Later presenters if tissue is salvageable ### Rapid pressure reduction can cut penumbral flow ### Decompression for malignant hemispheric, cerebellar ### Secondary prevention targets mechanism ## Intracranial haemorrhage ### Intracerebral: disruption, mass effect, oedema #### Sometimes ventricular obstruction ### Hypertension, amyloid angiopathy, anticoagulation ### Routine seizure prophylaxis not universally helpful ### Subarachnoid: sudden maximal headache #### Rebleeding, vasospasm, hydrocephalus, sodium ### Non-diagnostic imaging needs further testing ### Secure aneurysm early, give nimodipine ## Seizures and epilepsy ### Transient excessive or synchronous neuronal activity ### Focal: one hemisphere, impaired awareness, spread ### Generalised: bilateral networks from onset ### Epilepsy: enduring predisposition to unprovoked seizures ### Normal electroencephalogram does not exclude epilepsy ### Protect, airway, glucose, no restraint ### Status: about five minutes or no recovery #### Benzodiazepine, then longer-acting drug #### Persistent coma: non-convulsive status, EEG ### Safety: driving, water, work, pregnancy planning ### Refractory focal: surgery, stimulation, diet ## Raised intracranial pressure ### Rigid skull: brain, blood, cerebrospinal fluid ### Reserve exhausted, pressure rises sharply ### Perfusion pressure: mean arterial minus intracranial ### Headache, vomiting, sixth-nerve palsy, papilloedema #### Papilloedema may be absent acutely ### Hypertension, bradycardia, irregular breathing: late ### Elevate head, avoid hypotonic fluid, treat fever ### Hypertonic saline or mannitol reduce swelling briefly ### Brief hyperventilation: rescue bridge only ### Lumbar puncture dangerous with pressure gradients ## Infection and inflammation ### Meningitis: fever, headache, neck stiffness, rash #### Classic combinations may be incomplete ### Cultures and empirical antimicrobials without delay ### Autoimmune encephalitis: subacute memory, psychiatric ### Multiple sclerosis: dissemination in time and space #### Optic neuritis, brainstem syndromes, myelitis ### Steroids for relapse, disease-modifying therapy ## Peripheral neuropathy ### Distribution, fibre type, pathology, tempo ### Length-dependent: feet before hands ### Small fibre: burning pain, autonomic, normal studies ### Large fibre: vibration, proprioception, reflexes ### Conduction studies: axonal loss versus demyelination ### Guillain-Barre: rapid weakness, areflexia #### Monitor vital capacity, swallowing, rhythm #### Immunoglobulin or plasma exchange modifies disease #### Corticosteroids alone do not ## Neurodegeneration ### Alzheimer: episodic memory, amyloid and tau ### Lewy body: fluctuation, hallucinations, parkinsonism ### Frontotemporal: behaviour, executive, language ### Parkinson: dopaminergic and wider networks ### Motor neuron: upper and lower loss, sensation spared ### Consider reversible contributors ### Respect capacity, autonomy, personal goals