Acute Medicine: Reduced consciousness, seizures, headache and acute confusion

🩺 Reduced consciousness, seizures, headache and acute confusion. Acute neurological presentations are common and time-critical -"time is brain" in stroke, prolonged seizures cause brain damage, and meningitis and subarachnoid haemorrhage kill if missed. The front-door priorities are: protect the airway, check the glucose, stop seizures, treat infection early, and image the brain when needed. Detailed neurology is in the Neurology Emergencies and Stroke chapters; delirium in older people is in the Older Person chapter.
Your four questions for every patient: Is the airway safe -what is the GCS? Have I checked the glucose? Is there a focal deficit, seizure, fever or meningism that changes what I do right now? Does the patient need a CT head, an LP, or a specialist immediately?

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Approach to the Unconscious Patient

• ABCDE first:
  • Airway -open and protect; recovery position; GCS 8 or less -anaesthetic help (intubation).
  • Breathing -oxygen; look at the pattern (Cheyne–Stokes, Kussmaul in acidosis, slow in opioid toxicity).
  • Circulation -BP, ECG, IV access.
  • Disability -GCS, pupils, capillary glucose, limb movements and tone, seizures.
  • Exposure -temperature, rash, injuries, needle marks, patches, medical alert bracelets.
• Immediate treatments -glucose if low; naloxone if opioid toxicity suspected (pinpoint pupils, slow breathing); thiamine (Pabrinex) before or with glucose in malnourished or alcohol-dependent patients; treat seizures; antibiotics if meningitis possible.
• History -from witnesses, ambulance, family, GP records: onset (sudden or gradual), headache, seizures, trauma, drugs and alcohol, overdose, past history (diabetes, epilepsy, liver or kidney disease), recent illness.
• Examination -neck stiffness (don't move the neck if trauma), focal signs, pupils, fundi (papilloedema), breath smell (ketones, alcohol, fetor hepaticus), signs of liver disease, rashes.
• Investigations -capillary and lab glucose, ABG or VBG, U&E (sodium), calcium, LFTs, ammonia (if liver disease), FBC, CRP, blood cultures, paracetamol and salicylate levels, toxicology as needed, ECG, CT head (focal signs, trauma, unexplained coma), LP (meningitis or encephalitis once safe), EEG (non-convulsive status).

Causes of Coma

Group	Causes
Metabolic	Hypoglycaemia, hyperglycaemia (DKA, HHS), hyponatraemia, hypernatraemia, hypercalcaemia, uraemia, hepatic encephalopathy, hypercapnia, hypoxia, hypothermia, hypothyroidism (myxoedema coma), adrenal crisis, Wernicke's
Drugs and toxins	Alcohol, opioids, benzodiazepines, tricyclics, antipsychotics, GHB, carbon monoxide, overdose
Infection	Sepsis, meningitis, encephalitis, cerebral abscess, malaria (travel)
Structural (focal signs)	Stroke (brainstem, large hemisphere), intracerebral or subarachnoid haemorrhage, subdural or extradural haematoma, tumour, hydrocephalus
Seizures	Post-ictal state, non-convulsive status epilepticus
Other	Head injury, hypertensive encephalopathy, PRES, functional (psychogenic) unresponsiveness (diagnosis of exclusion)

• Pupils as clues -pinpoint (opioids, pontine haemorrhage); unilateral fixed dilated (third nerve compression -uncal herniation); bilateral fixed dilated (severe brain injury, anticholinergics, hypothermia, post-arrest); normal reactive pupils usually suggest metabolic or toxic causes.
• Locked-in syndrome (ventral pontine stroke) -conscious but can only move eyes vertically and blink -don't mistake for coma.

Hypoglycaemia

• Definition -blood glucose under 4 mmol/L (in people with diabetes); severe if help is needed to treat it.
• Symptoms -autonomic (sweating, tremor, palpitations, hunger, anxiety) and neuroglycopenic (confusion, odd behaviour, slurred speech, focal deficits -can mimic stroke, seizures, coma). Older people and those on beta-blockers or with long-standing diabetes may lose warning symptoms.
• Causes -insulin and sulphonylureas (commonest), missed meals, exercise, alcohol, kidney or liver failure, sepsis, adrenal insufficiency, hypopituitarism, insulinoma, post-gastric surgery (dumping), quinine, salicylate poisoning.
• Treatment (JBDS):
  • Conscious, can swallow -15–20 g fast-acting carbohydrate (e.g. 5–6 glucose tablets, 150–200 mL pure fruit juice); recheck in 10–15 minutes; repeat up to 3 times; then a starchy snack.
  • Unconscious, fitting or can't swallow -IV glucose (e.g. 75–80 mL of 20% or 150–160 mL of 10% over about 15 minutes), or IM glucagon 1 mg if no IV access (less effective in alcohol excess, liver disease, starvation and sulphonylurea toxicity).
  • Don't omit the next insulin dose (review it); sulphonylurea hypoglycaemia may recur for 24–72 hours -admit and monitor, glucose infusion ± octreotide.
• Thiamine -give IV Pabrinex to malnourished or alcohol-dependent patients (don't delay glucose).
• Non-diabetic hypoglycaemia -send glucose, insulin, C-peptide, ketones, cortisol and sulphonylurea screen during the episode.

Acute Stroke -the First Hours

• Recognise -sudden focal neurological deficit: FAST (Face, Arm, Speech, Time), visual field loss, ataxia, vertigo with other signs; ROSIER score in ED (over 0 suggests stroke).
• Exclude mimics -hypoglycaemia (check glucose first), seizures (Todd's paresis), migraine with aura, sepsis unmasking old deficits, brain tumour, subdural haematoma, functional disorders.
• Immediate actions (stroke pathway):
  • Time of onset or last known well (including waking with symptoms).
  • Urgent non-contrast CT head -haemorrhage vs ischaemia -with CT angiography if thrombectomy may be considered; CT perfusion for later presentations.
  • NIHSS score; ECG; bloods (glucose, FBC, clotting, U&E); anticoagulant history.
• Ischaemic stroke -reperfusion (NICE NG128):
  • Thrombolysis (alteplase or tenecteplase) within 4.5 hours of onset if no contraindications (haemorrhage, recent surgery or bleeding, anticoagulation, very high BP -lower to under 185/110 first).
  • Mechanical thrombectomy -for large vessel occlusion (anterior circulation) up to 6 hours, and selected patients up to 24 hours with favourable imaging (also basilar occlusion).
• Haemorrhagic stroke -reverse anticoagulation urgently (PCC and vitamin K for warfarin; reversal agents for DOACs); lower systolic BP to about 140 mmHg (within 6 hours, if presenting with systolic 150–220); neurosurgical referral for hydrocephalus or posterior fossa haemorrhage.
• General care -swallow screen before oral intake, aspirin 300 mg (after haemorrhage excluded; 24 hours after thrombolysis), oxygen only if hypoxic, glucose control, stroke unit admission, VTE prevention (intermittent pneumatic compression).

Transient Ischaemic Attack

• TIA -temporary focal neurological symptoms from ischaemia, fully resolving (usually within minutes to an hour), without infarction.
• Management (NICE NG128):
  • Aspirin 300 mg immediately (unless contraindicated or on anticoagulation -or bleeding disorder).
  • Specialist assessment within 24 hours of symptom onset for all suspected TIAs (ABCD2 scores are no longer used to triage).
  • Imaging -MRI (diffusion-weighted) in the TIA clinic; carotid imaging (carotid endarterectomy within 2 weeks for 50–99% symptomatic stenosis); ECG and monitoring for AF.
  • Secondary prevention -clopidogrel (or aspirin plus clopidogrel short-term for some), high-intensity statin, BP control, anticoagulation for AF, stop smoking.
• Crescendo TIAs (2 or more in a week), or TIA in a patient on anticoagulation -urgent admission or imaging.
• Driving -must not drive for 1 month after a TIA or stroke (car licence; longer for HGV).
• Mimics -migraine aura (spreading, positive symptoms), focal seizures, syncope, hypoglycaemia, transient global amnesia, labyrinthitis.

First Seizure

• Is it a seizure? -eyewitness account is vital (see TLoC on page 4) -syncope, cardiac arrhythmia and non-epileptic attacks are common mimics.
• Look for provoked causes:
  • Metabolic -hypoglycaemia, hyponatraemia, hypocalcaemia, hypomagnesaemia, uraemia.
  • Alcohol withdrawal (6–48 hours after stopping), drug withdrawal (benzodiazepines), illicit drugs (cocaine, amphetamines), drug toxicity (tramadol, tricyclics, bupropion, theophylline).
  • Infection -meningitis, encephalitis, cerebral abscess, fever (children).
  • Structural -stroke, haemorrhage, tumour, head injury.
  • Sleep deprivation; eclampsia (pregnancy or post-partum).
• Investigations -glucose, U&E, calcium, magnesium, FBC, CRP, prolactin (rarely helpful), ECG (long QT, Brugada, heart block), toxicology; CT head if focal signs, head injury, anticoagulated, persistent confusion, immunosuppressed, or not returning to normal; MRI and EEG via first-seizure clinic.
• Discharge if back to normal with no worrying features -urgent first-seizure clinic referral (within 2 weeks, NICE); safety advice (no baths alone, heights, swimming, operating machinery); must not drive and must inform the DVLA (usually 6 months off driving after a first unprovoked seizure for a car licence).
• Admit if -status, multiple seizures, not back to baseline, focal deficit, fever or suspected meningitis, significant injury, pregnancy, alcohol withdrawal.

Status Epilepticus

• Convulsive status epilepticus -a seizure lasting 5 minutes or more, or repeated seizures without recovery in between -a medical emergency (brain damage and death).
• Management (NICE NG217 and local protocols):

  Time	Action
  0–5 minutes	ABCDE, protect from injury (don't restrain), oxygen, recovery position when possible, check glucose, IV access, bloods (glucose, U&E, calcium, magnesium, FBC, antiepileptic levels, toxicology)
  5 minutes -first-line benzodiazepine	IV lorazepam (0.1 mg/kg, usually 4 mg) -or if no IV access, buccal midazolam 10 mg (or rectal diazepam 10–20 mg); repeat once after 5–10 minutes if still seizing
  Thiamine and glucose	IV Pabrinex if alcohol excess or malnutrition; glucose if hypoglycaemic
  About 20–25 minutes -second-line (if seizures continue after 2 doses of benzodiazepine)	IV levetiracetam (60 mg/kg, max 4,500 mg) or sodium valproate (40 mg/kg, max 3,000 mg -avoid in pregnancy and liver disease) or phenytoin (20 mg/kg with cardiac monitoring)
  About 45 minutes -refractory status	Rapid sequence induction (general anaesthesia -propofol or thiopental), ICU, EEG monitoring

• Find and treat the cause -antiepileptic non-adherence (check levels), alcohol withdrawal, infection, metabolic disturbance, stroke, tumour, drug toxicity, eclampsia (magnesium sulfate in pregnancy).
• Non-convulsive status -persisting confusion or reduced consciousness after a seizure, subtle twitching -EEG.
• Functional (dissociative) seizures -eyes closed (often resisting opening), side-to-side head movements, pelvic thrusting, long duration with fluctuating intensity, no cyanosis -avoid repeated benzodiazepines and intubation if confident; EEG where possible.

Approach to Acute Headache

• Most headaches are benign (migraine, tension-type) -the task is to spot secondary causes.
• Red flags (SNOOP and NICE):
  • Thunderclap headache -maximal within 1 minute -subarachnoid haemorrhage until proven otherwise (also reversible cerebral vasoconstriction, arterial dissection, cerebral venous thrombosis, pituitary apoplexy).
  • Fever, neck stiffness, rash -meningitis.
  • New focal neurology, seizures, confusion or reduced consciousness.
  • Papilloedema, headache worse lying down or on coughing/straining, morning vomiting -raised intracranial pressure.
  • Age over 50 with new headache, jaw claudication, scalp tenderness, visual symptoms -giant cell arteritis (ESR and CRP; steroids now).
  • Immunosuppression or cancer -abscess, metastases, opportunistic infection.
  • Head injury or anticoagulants -intracranial bleeding.
  • Pregnancy or post-partum -pre-eclampsia, cerebral venous thrombosis, post-dural puncture headache.
  • Red eye with headache and haloes -acute angle-closure glaucoma.
  • Carbon monoxide -several people affected, better away from home.
  • Progressive headache over weeks; change in pattern.
• Primary headaches in the acute setting:
  • Migraine -one-sided throbbing, nausea, photophobia, ± aura -paracetamol or NSAID plus triptan and antiemetic (metoclopramide, prochlorperazine); avoid opioids.
  • Cluster headache -severe unilateral orbital pain, 15–180 minutes, eye watering, ptosis, restless -high-flow oxygen (12–15 L/min) and subcutaneous or nasal triptan.
  • Medication overuse headache -regular analgesics or triptans; withdraw.

Subarachnoid Haemorrhage

• Thunderclap headache -sudden, severe ("worst ever"), maximal within 1 minute, often with vomiting, neck stiffness, photophobia, collapse, seizures or reduced consciousness; a "sentinel" headache may come first.
• Causes -ruptured berry aneurysm (most non-traumatic), AV malformations, trauma.
• Investigation (NICE NG228):
  • Non-contrast CT head as soon as possible -highly sensitive within 6 hours of onset.
  • If CT is normal and done within 6 hours -SAH is effectively excluded (with a good-quality scan reported by an experienced radiologist) -consider other causes.
  • If CT is normal and done after 6 hours -lumbar puncture at least 12 hours after headache onset -xanthochromia (bilirubin from broken-down red cells).
  • If SAH confirmed -CT angiography to find the aneurysm.
• Management -ABCDE, analgesia, antiemetics, nimodipine 60 mg 4-hourly (prevents delayed cerebral ischaemia), urgent referral to neurosurgery (coiling or clipping), BP control, monitor for hydrocephalus, rebleeding, hyponatraemia (see the Neurosurgery page).
• Other thunderclap causes -reversible cerebral vasoconstriction syndrome (RCVS -recurrent thunderclap headaches, triggers such as SSRIs and cannabis), cervical artery dissection (neck pain, Horner's), cerebral venous sinus thrombosis, pituitary apoplexy (visual loss, hypopituitarism -hydrocortisone), spontaneous intracranial hypotension.

Meningitis and Encephalitis

• Bacterial meningitis -fever, headache, neck stiffness, photophobia, vomiting, confusion, seizures, non-blanching rash (meningococcal); older people and immunosuppressed may present only with confusion.
• Organisms (adults) -Neisseria meningitidis, Streptococcus pneumoniae; Listeria in over-60s, pregnancy, immunosuppression, alcohol excess.
• Management (NICE NG240):
  • Don't delay antibiotics -give IV ceftriaxone 2 g (12-hourly) as soon as bacterial meningitis is suspected -within 1 hour; add amoxicillin if Listeria risk; adjust for recent travel (penicillin-resistant pneumococcus -add vancomycin).
  • Dexamethasone (10 mg IV 6-hourly) with or just before the first antibiotic dose in suspected pneumococcal or bacterial meningitis (not in septic shock from meningococcal sepsis without meningitis).
  • Blood cultures and meningococcal/pneumococcal PCR before antibiotics if no delay.
  • Lumbar puncture -as soon as safe (don't delay antibiotics); CT before LP if focal signs, seizures, papilloedema, reduced GCS (12 or less), immunosuppression.
  • Notify UKHSA; prophylaxis for close contacts (meningococcal).
• Viral meningitis (enteroviruses, HSV-2, VZV) -usually milder; supportive; aciclovir for HSV-2 or VZV in some.
• Encephalitis -altered behaviour, confusion, reduced consciousness, seizures, fever, focal signs; herpes simplex (HSV-1) commonest treatable cause -IV aciclovir 10 mg/kg 8-hourly immediately (adjust for kidney function); MRI (temporal lobe changes), LP (HSV PCR), EEG; also autoimmune encephalitis (anti-NMDA receptor -psychiatric symptoms, dyskinesias, seizures).
• Other infections -TB meningitis (subacute, cranial nerve palsies, low sodium), cryptococcal meningitis (HIV), brain abscess (focal signs, fever -imaging), cerebral malaria (travel).

Lumbar Puncture and CSF

• Contraindications -signs of raised intracranial pressure (papilloedema, focal signs, reduced or fluctuating GCS -CT first), coagulopathy or anticoagulants (platelets under about 40–50, INR over 1.5 -local policy), infection at the puncture site, shock or instability.
• Measure the opening pressure (lying on the side) -normal about 10–20 cmH₂O (raised in IIH, cryptococcal meningitis, venous sinus thrombosis).
• Send -cell count, Gram stain and culture, protein, glucose (with a paired blood glucose), viral PCR (HSV, VZV, enterovirus), xanthochromia (if SAH suspected), cytology, oligoclonal bands, TB and cryptococcal tests as indicated.

Feature	Normal	Bacterial	Viral	TB / fungal
Appearance	Clear	Cloudy, turbid	Clear	Clear or fibrin web
White cells	Under 5 /mm3	High -neutrophils	Raised -lymphocytes	Raised -lymphocytes
Protein	Under 0.45 g/L	High	Normal or mildly raised	High
Glucose (CSF:blood)	Over 0.6	Low (under 0.4)	Normal	Low

• Post-LP headache -worse on sitting or standing, better lying flat; fluids, caffeine, analgesia; epidural blood patch if persistent.

Acute Confusion

• Acute confusion -usually delirium (acute, fluctuating inattention from a medical cause) -a medical emergency (see the Older Person chapter on Delirium).
• Screen -4AT; collateral history (baseline cognition).
• Common causes -infection, drugs (opioids, sedatives, anticholinergics, steroids), alcohol withdrawal, hypoxia, hypercapnia, hypoglycaemia, hyponatraemia, hypercalcaemia, uraemia, liver failure (hepatic encephalopathy), urinary retention, constipation, pain, stroke, seizures (non-convulsive), head injury (subdural), thyroid disease, Wernicke's encephalopathy.
• Younger patients -also consider drugs and alcohol, encephalitis (including autoimmune), psychiatric illness (but always exclude organic causes first), thyroid storm, DKA.
• Investigations -glucose, FBC, U&E, calcium, LFTs, CRP, TFTs, B12, blood gas, cultures, ECG, chest X-ray, bladder scan, rectal examination; CT head if focal signs, head injury, anticoagulated or no clear cause; LP if meningitis or encephalitis suspected.
• Management -treat causes; non-drug measures (reorientation, family, glasses and hearing aids, sleep); sedation only if severe distress or risk (low-dose haloperidol -avoid in Parkinson's and Lewy body dementia); capacity assessment; safety.
• Acute behavioural disturbance and aggression -de-escalation first; look for organic causes; rapid tranquillisation per local policy (oral then IM lorazepam or antipsychotics), with monitoring; use of Mental Capacity Act or Mental Health Act as appropriate.

Alcohol Withdrawal and Wernicke's Encephalopathy

• Alcohol withdrawal -begins 6–24 hours after the last drink in dependent drinkers:
  • Early -tremor, sweating, anxiety, tachycardia, nausea, insomnia.
  • Withdrawal seizures -12–48 hours.
  • Delirium tremens -48–72 hours -confusion, visual hallucinations, agitation, fever, autonomic instability -mortality if untreated.
• Management (NICE CG100):
  • Assess with a validated scale (e.g. CIWA-Ar or GMAWS); chlordiazepoxide (symptom-triggered or fixed reducing regimen); lorazepam or oxazepam in severe liver disease or older people (shorter acting).
  • Delirium tremens -oral lorazepam (IV if needed); haloperidol if delirium persists; supportive care; consider critical care.
  • Fluids, electrolytes (magnesium, phosphate, potassium), glucose; look for infection, head injury, GI bleeding, pancreatitis, liver disease.
• Wernicke's encephalopathy (thiamine deficiency):
  • Classic triad -confusion, ataxia, ophthalmoplegia (nystagmus) -but all three are present in a minority; also hypothermia, hypotension, memory problems.
  • Treat on suspicion -high-dose IV thiamine (Pabrinex) -e.g. 2 pairs three times daily for 3–5 days (local protocol); give prophylactic Pabrinex to at-risk patients (alcohol excess, malnutrition, hyperemesis, after bariatric surgery).
  • Untreated -Korsakoff's syndrome (permanent amnesia, confabulation).
• Before discharge -brief intervention, alcohol liaison team, community alcohol services, medications to prevent relapse (acamprosate, naltrexone, disulfiram) -see the Psychiatry chapters.

Acute Weakness

Condition	Key features	Immediate action
Stroke	Sudden one-sided weakness, face and arm, speech	Stroke pathway -CT, thrombolysis or thrombectomy
Spinal cord compression	Back pain, bilateral leg weakness, sensory level, bladder or bowel dysfunction; cancer history (metastatic)	Whole spine MRI within 24 hours (urgently); dexamethasone 16 mg for metastatic compression; neurosurgery or oncology
Cauda equina syndrome	Saddle anaesthesia, urinary retention or incontinence, bilateral sciatica	Emergency MRI, surgical decompression
Guillain–Barré syndrome	Ascending symmetrical weakness, areflexia, after infection (Campylobacter); back pain, autonomic instability	FVC monitoring (ICU if under 20 mL/kg or falling); IVIG or plasma exchange
Myasthenic crisis	Fatigable weakness, ptosis, diplopia, bulbar weakness, breathlessness; triggers -infection, drugs (aminoglycosides, macrolides, magnesium, beta-blockers)	FVC monitoring, ICU, IVIG or plasma exchange; stop precipitating drugs
Hypokalaemic paralysis	Profound weakness with very low potassium (thyrotoxic periodic paralysis, diuretics)	Potassium replacement (careful in thyrotoxic -rebound)
Functional weakness	Inconsistent signs (Hoover's sign)	Positive diagnosis after excluding organic causes

• Respiratory muscle weakness -SpO₂ and blood gases deteriorate late -measure FVC (and single breath count) regularly; ICU referral early.

Acute Vertigo

• Acute vestibular syndrome -continuous vertigo for over 24 hours with nausea, vomiting, nystagmus and unsteadiness -usually vestibular neuritis, but posterior circulation stroke must be excluded.
• HINTS examination (in patients with ongoing vertigo and nystagmus -by trained clinicians):
  • Head Impulse test -abnormal (corrective saccade) suggests a peripheral cause; normal in a patient with acute vertigo is worrying (central).
  • Nystagmus -unidirectional horizontal (peripheral) vs direction-changing or vertical (central).
  • Test of Skew -vertical eye misalignment suggests central.
• Red flags for stroke -sudden onset with headache or neck pain, inability to walk, other neurological signs (diplopia, dysarthria, limb ataxia, facial numbness), vascular risk factors, central HINTS -urgent MRI.
• Benign paroxysmal positional vertigo -brief vertigo with head movement -Dix–Hallpike and Epley manoeuvre.
• Treatment -short-term vestibular sedatives (prochlorperazine, cyclizine) for severe nausea (no more than 3 days); vestibular rehabilitation; treat the cause.

Acute Neurology at a Glance

Situation	Key clues	Immediate action
Coma	GCS 8 or less	Airway; glucose; naloxone if opioids; CT head
Hypoglycaemia	Glucose under 4	Oral carbohydrate, IV glucose or IM glucagon
Ischaemic stroke	Sudden focal deficit	CT ± CTA; thrombolysis within 4.5 h; thrombectomy up to 6–24 h
TIA	Resolved focal symptoms	Aspirin 300 mg; specialist within 24 h
Status epilepticus	Seizure 5 minutes or more	Lorazepam or buccal midazolam (twice); then levetiracetam, valproate or phenytoin; RSI at 45 min
Thunderclap headache	Maximal within 1 minute	CT within 6 h; LP at 12 h if CT later and normal
Bacterial meningitis	Fever, neck stiffness, rash	Ceftriaxone 2 g ± amoxicillin; dexamethasone
Encephalitis	Confusion, fever, seizures	IV aciclovir; MRI, LP
Alcohol withdrawal	Tremor, sweating, hallucinations	Chlordiazepoxide; Pabrinex
Wernicke's	Confusion, ataxia, nystagmus	High-dose IV Pabrinex
Cord compression	Back pain, leg weakness, sensory level	MRI whole spine; dexamethasone 16 mg
Guillain–Barré	Ascending weakness, areflexia	FVC; IVIG
Acute vertigo	Continuous vertigo with nystagmus	HINTS; MRI if central features

Spot the Diagnosis

Clue	Diagnosis
Right-sided weakness that resolves with IV glucose	Hypoglycaemia (stroke mimic)
Coma with pinpoint pupils and RR 6	Opioid toxicity
Coma, unilateral fixed dilated pupil, falling GCS	Uncal herniation -urgent CT and neurosurgery
Drowsy, flapping tremor and jaundice	Hepatic encephalopathy
Only able to move eyes vertically and blink, fully aware	Locked-in syndrome
Facial droop and arm weakness for 20 minutes, now normal	TIA -aspirin, specialist within 24 h
Seizure on day 2 of admission in a heavy drinker	Alcohol withdrawal seizure
Seizure lasting 8 minutes despite one dose of lorazepam	Status epilepticus -repeat benzodiazepine
Persistent drowsiness after a seizure with subtle eye twitching	Non-convulsive status -EEG
Sudden worst-ever headache while lifting, CT normal at 2 hours	SAH effectively excluded (if good-quality CT within 6 hours)
Xanthochromia on LP 14 hours after headache	Subarachnoid haemorrhage
Recurrent thunderclap headaches after starting an SSRI	Reversible cerebral vasoconstriction syndrome
Headache, visual loss and low sodium with a pituitary mass	Pituitary apoplexy -hydrocortisone
Fever, neck stiffness, CSF neutrophils and low glucose	Bacterial meningitis
Fever, odd behaviour and seizures with temporal lobe changes on MRI	HSV encephalitis -aciclovir
Confusion, ataxia and nystagmus in a malnourished drinker	Wernicke's encephalopathy
Back pain, leg weakness and urinary retention with prostate cancer	Metastatic spinal cord compression
Ascending weakness with absent reflexes after diarrhoea	Guillain–Barré syndrome
Ptosis, diplopia and breathlessness after gentamicin	Myasthenic crisis
Continuous vertigo with a normal head impulse test and skew deviation	Posterior circulation stroke

Exam-style Scenarios

1. A 74-year-old man has sudden left arm and face weakness and slurred speech, starting 90 minutes ago. Glucose 6.2. BP 172/94. He takes no anticoagulants.
Answer: Acute ischaemic stroke (until proven otherwise) within the thrombolysis window.

• Stroke team alert; urgent non-contrast CT head and CT angiography.
• If no haemorrhage and no contraindications -thrombolysis (alteplase or tenecteplase); thrombectomy if large vessel occlusion.
• Swallow screen, stroke unit admission; aspirin 24 hours after thrombolysis; secondary prevention.

2. A 32-year-old woman with epilepsy has been fitting for 7 minutes. She has no IV access.
Answer: Convulsive status epilepticus.

• ABCDE, oxygen, check glucose; buccal midazolam 10 mg; get IV access; repeat a benzodiazepine (IV lorazepam 4 mg) after 5–10 minutes if still fitting.
• If still seizing -IV levetiracetam 60 mg/kg (or valproate or phenytoin -avoid valproate if pregnant or could be); anaesthetics and ICU by about 45 minutes.
• Look for causes (missed medication, infection, pregnancy -eclampsia, alcohol); check antiepileptic levels.

3. A 45-year-old woman has a sudden severe headache during exercise 8 hours ago, with vomiting. She is alert with mild neck stiffness. CT head at 8 hours is normal.
Answer: Suspected subarachnoid haemorrhage -CT after 6 hours is not enough.

• Lumbar puncture at least 12 hours after onset -xanthochromia.
• If positive -CT angiography and neurosurgical referral; nimodipine.
• If negative -consider other thunderclap causes (RCVS, dissection, venous sinus thrombosis -CT or MR angiography/venography as indicated).

4. A 66-year-old man is brought in confused with a temperature of 39°C, neck stiffness and a GCS of 12. He had a seizure in the ambulance.
Answer: Suspected bacterial meningitis or encephalitis.

• Immediate IV ceftriaxone 2 g plus amoxicillin (Listeria -over 60), dexamethasone, and IV aciclovir (encephalitis possible); blood cultures first if no delay.
• CT head before LP (seizure, reduced GCS); LP when safe (cell count, glucose, protein, Gram stain, PCR including HSV).
• Critical care if GCS falling; notify UKHSA if bacterial meningitis; contact prophylaxis for meningococcal disease.

5. A 52-year-old man with alcohol dependence was admitted 2 days ago with a fall. He is now agitated, sweaty, tremulous and seeing insects on the walls. HR 125, temperature 38°C.
Answer: Delirium tremens.

• Benzodiazepines -oral lorazepam or chlordiazepoxide (IV lorazepam if unable to take orally) per protocol; IV fluids; correct potassium, magnesium and phosphate; check glucose.
• High-dose IV Pabrinex (Wernicke's prevention and treatment).
• Look for other causes (infection, head injury from the fall -CT head, GI bleed, pancreatitis); consider HDU or ICU; alcohol liaison team before discharge.

Key Points

• In reduced consciousness -protect the airway (GCS 8 or less), check glucose, consider naloxone and thiamine.
• Hypoglycaemia (under 4 mmol/L) can mimic stroke, seizures and coma.
• Stroke -time is brain; CT ± CTA; thrombolysis within 4.5 hours; thrombectomy for large vessel occlusion up to 6 (selected up to 24) hours.
• TIA -aspirin 300 mg and specialist review within 24 hours; ABCD2 no longer used.
• First seizure -look for provoking causes, ECG for all, first-seizure clinic, DVLA advice.
• Status -benzodiazepine at 5 minutes, repeat once, then levetiracetam, valproate or phenytoin; anaesthesia by about 45 minutes.
• Thunderclap headache -CT within 6 hours; if later and normal, LP at 12 hours for xanthochromia.
• Headache red flags -thunderclap, fever and neck stiffness, focal signs, raised ICP features, over 50 (GCA), immunosuppression, anticoagulants.
• Suspected bacterial meningitis -ceftriaxone without delay; amoxicillin if Listeria risk; dexamethasone.
• Suspected encephalitis -IV aciclovir immediately.
• CT before LP with focal signs, seizures, papilloedema, reduced GCS or immunosuppression.
• Bacterial CSF -neutrophils, high protein, low glucose; viral -lymphocytes, normal glucose.
• Alcohol withdrawal -chlordiazepoxide; delirium tremens at 48–72 hours; Pabrinex for Wernicke's.
• Acute weakness -cord compression (MRI, dexamethasone), GBS and myasthenia (FVC, not SpO₂).
• Acute vertigo -HINTS; a normal head impulse test in acute vertigo is worrying.

Guidelines and Further Reading

• NICE NG128: Stroke and TIA in over 16s -diagnosis and initial management
• National Clinical Guideline for Stroke for the UK and Ireland (2023)
• NICE NG217: Epilepsies in children, young people and adults (including status epilepticus)
• NICE NG228: Subarachnoid haemorrhage caused by a ruptured aneurysm
• NICE NG240: Meningitis (bacterial) and meningococcal disease
• Association of British Neurologists and British Infection Association: Management of suspected viral encephalitis
• NICE CG100: Alcohol-use disorders -diagnosis and management of physical complications
• Joint British Diabetes Societies: Hospital management of hypoglycaemia in adults with diabetes
• NICE NG234: Spinal metastases and metastatic spinal cord compression
• BNF -for current doses