PassFinals
Neurology

Stroke

Sudden focal neurological loss from arterial occlusion or vessel rupture: occlusion leaves a dying core around which viable brain can still be rescued, rupture makes any antithrombotic dangerous.

Definition

Acute neurological dysfunction caused by focal central nervous system injury of vascular origin: cerebral infarction, intracerebral haemorrhage or subarachnoid haemorrhage. A transient ischaemic attack is the same clinical syndrome from cerebral, spinal or retinal ischaemia, resolving completely and without acute infarction.

Epidemiology

Stroke is common, rises steeply with age and is a leading cause of death and acquired adult disability in the UK. About four in five are ischaemic. Modifiable risk factors are hypertension, atrial fibrillation, smoking, diabetes, dyslipidaemia, obesity, excess alcohol and previous stroke or TIA.

Pathophysiology

Occlusion by in-situ thrombus, embolus, large-artery atheroma or small-vessel disease produces an infarct core with a surrounding penumbra whose survival depends on collateral flow and time. Rupture produces haematoma, mass effect and sometimes hydrocephalus or raised intracranial pressure. The syndrome reflects the territory involved and the volume of tissue injured.

First principles

The clock is the history, so take it before you take anything else

Every reperfusion decision is measured from the time the person was last known to be well, not from the time they were found. Establish that time, then the anticoagulants and the pre-stroke function. A stroke pathway that starts with a full clerking has already lost the treatment window.1,2,3

Ischaemia and haemorrhage look identical and need opposite treatments

Occlusion starves tissue of oxygen and glucose; rupture injures it directly and adds mass effect. Nothing at the bedside separates them reliably, which is why the plain CT comes before aspirin and before thrombolysis. The scan is not confirming your diagnosis, it is choosing between two incompatible treatments.1,2

The penumbra is why the windows exist, and why imaging can stretch them

Around the irreversibly infarcted core sits hypoperfused but living brain, kept alive by collaterals and shrinking by the minute. Fixed time windows are a crude proxy for how much of that tissue survives. Perfusion imaging measures it directly, which is how selected people are treated well beyond 4.5 hours.1,4,5,2

The deficit names the vessel

Middle cerebral artery (MCA) territory infarction gives face and arm weakness, with aphasia if the dominant hemisphere is involved. Anterior cerebral artery (ACA) disease is leg-predominant. Posterior circulation disease gives vertigo, diplopia, ataxia, dysarthria or crossed brainstem signs. The Oxfordshire Community Stroke Project (OCSP, or Bamford) classification is the clinical shorthand for these territories before imaging. Its four categories are total anterior circulation syndrome (TACS), partial anterior circulation syndrome (PACS), posterior circulation syndrome (POCS) and lacunar syndrome (LACS).2,3

After the hyperacute decision, the stroke unit is the treatment

Most people with stroke are not thrombolysed and not thrombectomised, and their outcome still turns on where they are admitted. A specialist unit screens swallowing before anything is swallowed, holds glucose, oxygen and hydration inside narrow limits, prevents aspiration and thrombosis, and starts rehabilitation. That is an intervention, not a ward round.1,6,2

Presentation

Sudden focal neurological loss: unilateral weakness, facial droop, dysphasia, visual field loss, dysarthria, ataxia or neglect, usually maximal at onset. Severe headache, vomiting, meningism or falling consciousness suggests haemorrhage.1,3,2

Cardinal features

  • Sudden unilateral facial, arm or leg weakness or numbness
  • Sudden dysphasia, dysarthria or difficulty understanding speech
  • Sudden visual field loss, monocular visual loss or diplopia
  • Sudden vertigo, ataxia, dysphagia or crossed brainstem signs
  • Neglect, apraxia or other higher cortical dysfunction
  • Identical symptoms that have already resolved, which is a TIA until a specialist says otherwise

Red flags

  • Severe headache at onset, vomiting, meningism, seizure or falling consciousness, suggesting haemorrhage
  • Progressive or fluctuating deficit, papilloedema or fever
  • Airway compromise or inability to protect the airway
  • Anticoagulant exposure or a known bleeding tendency
  • Capillary glucose below 4.0 mmol/L, which is a treatable mimic
  • Wake-up or unwitnessed onset: record the midpoint of sleep and refer, because perfusion imaging may still open a treatment window

Investigations

Recognition, and the last known well time

Use FAST (Face, Arm, Speech, Time) outside hospital and ROSIER (Recognition of Stroke in the Emergency Room) in the emergency department: both separate stroke from mimic, neither decides treatment. Record the exact time last known well, anticoagulants, pre-stroke function and comorbidity.

Expected finding: A persisting focal deficit triggers the hyperacute pathway. Complete resolution within 24 hours is managed as suspected TIA. A negative FAST does not exclude stroke.

1,2,3

Capillary blood glucose

Hypoglycaemia causes focal deficits and reverses in minutes, so NICE makes excluding it a standalone recommendation. Below 4.0 mmol/L, give 15 to 20 g of rapid-acting carbohydrate if the person is alert and can swallow, then recheck after 10 to 15 minutes.

Expected finding: Correction that abolishes the deficit points to a mimic. Persisting focal signs after correction still need the stroke pathway. NICE targets glucose at 4 to 11 mmol/litre; the 2023 national stroke guideline uses 5 to 15 mmol/L. Follow the hyperacute stroke protocol and avoid hypoglycaemia.

1,7,2

Non-enhanced CT head

CT answers one question: is there blood? Perform it immediately for possible thrombolysis or thrombectomy, anticoagulant treatment, known bleeding tendency or GCS below 13. Also for progressive or fluctuating symptoms, papilloedema, neck stiffness, fever, or severe headache at onset. Otherwise scan within 24 hours, aiming to image everyone within 1 hour of arrival.

Expected finding: Hyperdense fresh blood confirms haemorrhage. Early ischaemia is often invisible, so a normal scan does not exclude infarction. What it does is permit aspirin and thrombolysis.

1,2

CT angiography, and perfusion imaging in late presentations

If thrombectomy might be indicated, perform CT angiography (CTA) from aortic arch to skull vertex immediately after the plain CT, without delaying thrombolysis. Add CT perfusion or the MR equivalent when thrombectomy might be indicated beyond 6 hours, or for a wake-up stroke.

Expected finding: CTA or MR angiography (MRA) shows the occluded proximal vessel. Perfusion imaging separates a small irreversible core from a larger salvageable penumbra, which is what licenses treatment beyond the early window.

1,2

Score the deficit and the pre-stroke function

The National Institutes of Health Stroke Scale (NIHSS) grades how severe the deficit is; the modified Rankin scale (mRS) grades how independent the person was before the stroke. NICE uses both to select thrombectomy candidates, and NIHSS again to select decompressive hemicraniectomy.

Expected finding: NICE uses a pre-stroke mRS below 3 with NIHSS above 5 for thrombectomy. The 2023 national stroke guideline is stricter and also uses ASPECTS imaging criteria, so the stroke team applies the current local pathway. NIHSS above 15 with item 1a at 1 or more is one hemicraniectomy criterion.

1,2

ECG, cardiac monitoring and targeted bloods

Monitor for atrial fibrillation, the commonest treatable cardioembolic source. Send FBC, U&E, glucose and clotting studies when anticoagulant exposure or coagulopathy is possible. Do not delay reperfusion waiting for results.

Expected finding: Atrial fibrillation moves secondary prevention from antiplatelet to anticoagulant. Thrombocytopenia, coagulopathy or renal impairment changes acute treatment.

1,2

Swallow screen before anything by mouth

Screen swallowing with a validated tool within 4 hours of arrival, by a trained professional, before any oral food, fluid or medicine. If the screen is abnormal, arrange specialist swallow assessment preferably within 24 hours and no more than 72 hours afterwards.

Expected finding: A normal screen allows oral intake and oral medicines. An abnormal screen means an alternative route for nutrition, hydration and drugs, plus a review of every medicine formulation.

1,2

Carotid imaging and the mechanism

Anyone considered a candidate for carotid intervention after specialist assessment should have carotid imaging within 24 hours of that assessment. The report must state whether NASCET (North American Symptomatic Carotid Endarterectomy Trial) or ECST (European Carotid Surgery Trial) criteria were used, because the same artery scores differently under each.

Expected finding: Symptomatic stenosis of 50% to 99% by NASCET, or 70% to 99% by ECST, means urgent referral for endarterectomy plus best medical treatment. Below those figures, medical treatment only.

1,8

Management

StepDetailSource
Activate the hyperacute pathway and hold the physiologyPre-alert and admit directly to a specialist acute stroke unit. Record last known well, anticoagulants and pre-stroke function. Nothing by mouth until swallowing is screened. Give oxygen only if saturation falls below 95%. NICE targets glucose at 4 to 11 mmol/litre; the national stroke guideline uses 5 to 15 mmol/L. Follow the hyperacute protocol and avoid hypoglycaemia.1,2,3NICE NG128 recommendations 1.3.1, 1.5.1 and 1.5.2; National Clinical Guideline for Stroke for the UK and Ireland 2023, section 3.10
Image immediately and answer the reperfusion questionPerform non-enhanced CT immediately for: possible thrombolysis or thrombectomy, anticoagulation, bleeding tendency, GCS below 13, progressive or fluctuating symptoms, papilloedema, neck stiffness or fever, severe headache at onset. Otherwise scan within 24 hours. Add CT angiography if thrombectomy is possible, plus CT perfusion beyond 6 hours.1,2NICE NG128 recommendations 1.3.2 and 1.3.3; National Clinical Guideline for Stroke 2023, section 3.4
Thrombolyse within 4.5 hours once haemorrhage is excludedAlteplase 900 micrograms/kg intravenously, maximum 90 mg: 10% as a bolus, the remainder infused over 60 minutes. Tenecteplase is the single-bolus alternative, dosed by weight band from 15 mg below 60 kg to 25 mg at 90 kg or more. Start within 4.5 hours of onset, and reduce blood pressure below 185/110 mmHg first.1,4,5,9,10,2NICE NG128 recommendation 1.5.10; NICE TA264 recommendation 1.1 and TA990 recommendation 1.1; BNF alteplase and tenecteplase monographs
Apply the exclusions, and know the extended windowExclude anyone on a direct oral anticoagulant (DOAC), unless they take dabigatran and the prothrombin time and activated partial thromboplastin time are both normal. Do not reverse a DOAC in order to thrombolyse. Between 4.5 and 9 hours, or within 9 hours of the midpoint of sleep, thrombolysis is a specialist decision made on perfusion mismatch imaging.2National Clinical Guideline for Stroke 2023, section 3.5 recommendation B and Table 3.5.1
Refer for thrombectomy on the vessel, the clock and two scoresOffer thrombectomy within 6 hours for a proximal anterior circulation occlusion on CT angiography or MR angiography, with thrombolysis alongside. Offer it from 6 to 24 hours, including wake-up stroke, if imaging shows salvageable tissue. Consider it up to 24 hours for basilar or posterior cerebral artery occlusion.1,2NICE NG128 recommendations 1.4.5, 1.4.6 and 1.4.7
Check the two thrombectomy selection gatesNICE gates all three thrombectomy windows on a pre-stroke modified Rankin scale below 3 and NIHSS above 5. The 2023 national guideline uses stricter functional thresholds and ASPECTS imaging criteria. The stroke team applies the current pathway, weighing clinical status, vessel, time and established infarction; do not deny referral from one score alone.1,2NICE NG128 recommendation 1.4.8
Give aspirin once haemorrhage is excludedAspirin 300 mg orally, or rectally or by enteral tube if dysphagic, within 24 hours. Continue 300 mg daily until 2 weeks after onset, then start long-term treatment. After thrombolysis, wait 24 hours and exclude significant haemorrhage first. Add a proton pump inhibitor for previous aspirin dyspepsia, or an alternative antiplatelet if genuinely aspirin-intolerant.1,2,11NICE NG128 recommendations 1.4.9, 1.4.10 and 1.4.11; National Clinical Guideline for Stroke 2023, section 3.5 recommendation O
Treat suspected TIA as an emergencyGive aspirin 300 mg immediately and refer for specialist assessment within 24 hours. Do not use ABCD2 or any other score to stratify risk or ration urgency: they do not discriminate between low and high risk. Do not order a CT head unless another diagnosis is suspected; MRI after specialist assessment is the imaging of choice.1,2,11NICE NG128 recommendations 1.1.4, 1.1.5, 1.1.6, 1.2.1 and 1.2.2; National Clinical Guideline for Stroke 2023, section 3.2
Start dual antiplatelet treatment after TIA or minor strokeWithin 24 hours, at low bleeding risk: clopidogrel 300 mg then 75 mg daily, plus aspirin 300 mg then 75 mg daily for 21 days. Then clopidogrel 75 mg alone. Ticagrelor 180 mg then 90 mg twice daily with 30 days of aspirin is the alternative. If dual treatment is unsuitable, clopidogrel 300 mg then 75 mg daily.2,12,13,11National Clinical Guideline for Stroke 2023, section 3.3 recommendation B; BNF clopidogrel, ticagrelor and aspirin monographs
Reverse and control blood pressure in intracerebral haemorrhageReverse warfarin with prothrombin complex concentrate (PCC) and intravenous vitamin K. Use idarucizumab for dabigatran; consider 4-factor PCC for factor Xa inhibitors. For systolic 150 to 220 mmHg within 6 hours, NICE targets 140 or lower with no more than a 60 mmHg fall in one hour; national guidance targets 130 to 139. Use the hyperacute protocol.1,2NICE NG128 recommendations 1.4.16, 1.5.4 and 1.5.6; National Clinical Guideline for Stroke 2023, section 3.6 recommendations A and B
Escalate to neurosurgery on the criteria, not on instinctDo not lower blood pressure rapidly if there is a structural cause, GCS below 6, planned haematoma evacuation, or a massive haematoma with poor expected prognosis. Refer previously fit people with hydrocephalus. Consider decompressive hemicraniectomy within 48 hours for NIHSS above 15, reduced consciousness, and at least 50% MCA territory infarction.1,2NICE NG128 recommendations 1.5.7, 1.9.3 and 1.9.5
Feed, mobilise and prevent the ward complicationsScreen swallowing within 4 hours, before anything oral. If abnormal, get specialist assessment within 24 hours and at most 72. Start nasogastric feeding within 24 hours of admission if oral intake is unsafe, unless the person has had thrombolysis. Do not mobilise at high intensity in the first 24 hours.1,2NICE NG128 recommendations 1.6.1, 1.6.2, 1.6.4 and 1.7.3; National Clinical Guideline for Stroke 2023, section 3.10 recommendation E
Anticoagulate atrial fibrillation on the disabling axisDo not anticoagulate acute stroke routinely. In disabling ischaemic stroke with atrial fibrillation, give aspirin 300 mg for the first 2 weeks before anticoagulation is considered. In non-disabling stroke or TIA with atrial fibrillation, anticoagulate as soon as intracranial bleeding is excluded, using a rapid-onset agent.1,2,11NICE NG128 recommendations 1.4.12 and 1.4.17; National Clinical Guideline for Stroke 2023, section 3.3 recommendation D
Deliver mechanism-led secondary preventionNon-cardioembolic stroke or TIA: clopidogrel 75 mg daily long term, or aspirin 75 mg daily if clopidogrel is not tolerated. Atorvastatin 80 mg daily, started immediately after TIA or minor stroke but not immediately in acute stroke, targeting low-density lipoprotein (LDL) cholesterol below 1.8 mmol/L. Aim for clinic systolic blood pressure below 130 mmHg.8,1,12,14,11National Clinical Guideline for Stroke 2023, sections 5.5 and 5.6 and the blood pressure recommendations; NICE NG128 recommendations 1.4.21 and 1.4.22; BNF atorvastatin and clopidogrel monographs
Rehabilitate, follow up and safety-netOffer needs-based rehabilitation for at least 3 hours a day on at least 5 days a week, covering physiotherapy, occupational therapy and speech and language therapy. Early supported discharge continues specialist team rehabilitation at home rather than ending it. Tell patients and carers to call 999 for any new FAST symptoms.6,3NICE NG236 recommendations 1.1.1 and 1.2.16; NHS stroke information

Illustrations

Vascular territories and the Oxfordshire (Bamford) classificationDiagram of the anterior, middle and posterior cerebral artery territories mapped against the Oxfordshire Community Stroke Project categories. These are total anterior circulation syndrome (TACS), partial anterior circulation syndrome (PACS), posterior circulation syndrome (POCS) and lacunar syndrome (LACS).PassFinals · original
CT head in acute strokeNon-contrast CT of the head performed in acute stroke.Hellerhoff, Wikimedia Commons · CC-BY-SA-3.0
Ischaemic core and penumbraPerfusion diagram showing an infarcted core surrounded by salvageable penumbra sustained by collateral flow, shrinking over time.PassFinals · original

Differentials

Hypoglycaemia or another metabolic disturbance

Focal deficit that resolves on correcting the glucose. Persisting focal signs after correction still need the stroke pathway.

Seizure with Todd paresis

Witnessed convulsion, tongue biting, post-ictal confusion or recurrent stereotyped episodes. Stroke itself can provoke seizures.

Migraine with aura

Positive symptoms spreading over minutes and fully reversible, in a recurrent migraine pattern. Abrupt maximal negative deficits are atypical.

Functional neurological disorder

Internal inconsistency and incongruity on expert examination. Never a first-pass diagnosis before structural causes have been excluded.

Subarachnoid haemorrhage

Thunderclap headache maximal within seconds, meningism, vomiting or reduced consciousness rather than a focal limb deficit.

Space-occupying lesion or subdural haematoma

Subacute or fluctuating progression, headache worse on waking, or a history of head injury or anticoagulation.

Complications

  • Cerebral oedema, raised intracranial pressure and herniation
  • Haemorrhagic transformation or recurrent intracranial bleeding
  • Aspiration pneumonia, dysphagia, malnutrition and dehydration
  • Deep vein thrombosis and pulmonary embolism
  • Seizures, depression, anxiety, fatigue and cognitive impairment
  • Persistent disability, communication difficulty and recurrent stroke

Prognosis

Outcome depends on stroke type, lesion size and site, pre-stroke function, complications and time to reperfusion. Stroke-unit care and timely reperfusion reduce disability; recovery continues over months with rehabilitation. Recurrence risk is highest early, which is why secondary prevention starts before discharge.

Guidelines

  • Stroke and transient ischaemic attack in over 16s: diagnosis and initial management (NG128) (NICE, 2019)
  • Alteplase for treating acute ischaemic stroke (TA264) (NICE, 2012)
  • Tenecteplase for treating acute ischaemic stroke (TA990) (NICE, 2024)
  • National Clinical Guideline for Stroke for the UK and Ireland (Intercollegiate Stroke Working Party, 2023)
  • Stroke rehabilitation in adults (NG236) (NICE, 2023)

References

  1. NICE NG128: Stroke and transient ischaemic attack in over 16s, recommendations (NG128, recommendations 1.1.1 to 1.9.7; recommendations 1.4.2 and 1.4.3 amended 2025)Published 1 May 2019 | Updated 13 Apr 2022
  2. National Clinical Guideline for Stroke for the UK and Ireland: Acute care (Intercollegiate Stroke Working Party, 2023 edition, chapter 3 Acute care (sections 3.2, 3.3, 3.4, 3.5 including Table 3.5.1, 3.6 and 3.10))
  3. NHS: Symptoms of a stroke (NHS condition information, patient-facing; used for public recognition and safety-netting only)Published 19 Sept 2024 | Updated 21 Nov 2024
  4. NICE TA264: Alteplase for treating acute ischaemic stroke (Technology appraisal TA264, recommendation 1.1)
  5. NICE TA990: Tenecteplase for treating acute ischaemic stroke (Technology appraisal TA990, recommendations 1.1 and 1.2)
  6. NICE NG236: Stroke rehabilitation in adults, recommendations (NG236, recommendations 1.1.1 and 1.2.16)
  7. Joint British Diabetes Societies for Inpatient Care, The Hospital Management of Hypoglycaemia in Adults with Diabetes Mellitus (JBDS 01, revised January 2023; treatment thresholds and doses for hypoglycaemia in hospital, including rapid-acting carbohydrate, intravenous glucose and intramuscular glucagon)
  8. National Clinical Guideline for Stroke for the UK and Ireland: Long-term management and secondary prevention (Intercollegiate Stroke Working Party, 2023 edition, chapter 5 (blood pressure, section 5.5 lipid modification, section 5.6 antiplatelet treatment))
  9. BNF: Alteplase (BNF medicine monograph, acute ischaemic stroke indication and blood pressure monitoring requirement)
  10. BNF: Tenecteplase (BNF medicine monograph, acute ischaemic stroke indication using the 25 mg (5000 unit) vial)
  11. BNF: Aspirin (BNF medicine monograph, stroke and transient ischaemic attack indications)
  12. BNF: Clopidogrel (BNF medicine monograph, transient ischaemic attack and minor ischaemic stroke indications)
  13. BNF: Ticagrelor (BNF medicine monograph, transient ischaemic attack and minor ischaemic stroke indications (unlicensed use))
  14. BNF: Atorvastatin (BNF medicine monograph, secondary prevention of cardiovascular events)

Evidence checked: 2026-08-07

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.