1. SDMH EMC 2015
Acute Headache

2. Objectives
Key assessment features to ascertain in acute headache – differential causes
When to consider neuroimaging
Become familiar with subarachnoid haemorrhage (SAH) workup
Understand the features of infective headaches
Features that may suggest uncommon but important diagnoses

3. Broad differential causes

4. Assessment History EXAM ABCD – primarily GCS BP and T
Acuity of onset
Prodromal features – fever, ‘flu’, nausea, visual problems
Syncope, meningism, eye pain, focal neurology, facial pain, seizures
Headache pattern
Family history – Migraine, SAH
Medications – immunosuppressant's, recent antibiotics
ABCD – primarily GCS
BP and T
Neck rigidity/photophobia
Detailed neurological exam
Facial sinuses
Eyes
Temporal artery tenderness

5. Investigation Pathology – largely unhelpful.
Serum Na, BSL and ESR/CRP may assist with some differentials
Imaging – CT head test of choice if indicated
Invasive – Lumbar puncture if SAH, meningitis, encephalitis or Idiopathic intracranial hypertension considered

6. Imaging algorithm

7. More detail
Historical
EXAm

8. About migraine… Classic – unilateral, throbbing, nauseating.
Common – generalized headache, deteriorating with time
Headache preceded by aura and/or nausea
Family history. Onset in adolescence or young adulthood
Stereotypical – patient can recognise it.
Migraine sufferers can also suffer other neuropathology eg SAH

9. Management 1st line - NSAID – PO/PR and Paracetamol 2nd line –
Metoclopromide 10mg IM/IV OR
Prochlorperazine 12.5mg IM/IV OR
Droperidol IM/IV
3rd line – Chlorpromazine 12.5 mg IV in IV fluids Repeat x 1 if ineffective
Rehydrate – fluids often helpful
If failing to settle, consider alternate diagnosis, senior input
Triptans – expensive, frequently ineffective in ED population
Ergotamine unavailable

10. Case scenario 44 yr old female Smoker
Sudden onset severe R sided headache whilst sitting reading a book 3 hrs earlier
Associated nausea, vomited x 2
Otherwise well
BUT….
4 x sisters with ‘bleeds into brain’ – 2 deceased from aneurysms in NZ

11. Subarachnoid haemorrhage
80% due to aneurysm
Median age 50
Smoking 4-5 x risk
Typically ‘worst ever’ headache
Reaching maximal severity immediately
Nausea/vomiting/syncope/seizure raise suspicion
May only have headache
Headache may dissipate within hours-days
Causes 12-25% of thunderclap headaches

12. Subarachnoid haemorrhage
Exam – often normal
Photophobia/nuchal rigidity
Decreasing level of consciousness , worse outcome
Thus need to avoid missing the ‘sentinel bleed’
Re-bleed - 1 day to 1 month later

13. Investigation CT head First line test – non contrast CT head
Positive result on CT  CT angiography
Will help to determine neurosurgical plan

14. To LP or not to LP?
CT sensitivity traditionally quoted as ~ 90% at 4-12hrs after headache, falling with time
CSF testing for RBC breakdown (xanthochromia) - gold standard
‘Standard practice’ – if CT negative do LP 12 hrs from onset headache
Perry et al 2011 – 100% CT sensitivity < 6hrs headache  no LP needed if presenting under 6 hrs
LP may find alternate pathology

15. Management
Definitive treatment - interventional neuroradiology or neurosurgeon – transfer
Analgesia
Antiemetic
Avoid hypertension and hypotension (?140>BP>100)
?Seizure prophylaxis
Nimodipine PO within 96 hrs

16. Bacterial meningitis Headache +fever +meningism
Frequently following URTI
May deteriorate quickly, or have persistent headache for days
Altered LoC significant feature – drowsiness
Vomiting common.
Seizure 25% patients
Rash in meningococcemia; may not be present in isolated meningitis

17. Management Meningitis considered likely THEN
Dexamethasone 10mg IV then
Ceftriaxone 2g IV AND
Penicillin 2.4g IV IF immunocompromised, age >50, alcoholic, pregnant or debilitated
Steroid BEFORE antibiotics.
Avoid antibiotic delay
10% all-comer mortality (20% pneumococcus)
25% neurological morbidity

18. To LP or not to LP? Theoretical concerns about cerebral herniation
Considered contraindicated in high ICP (e.g. low GCS)
If signs ICP  CT head
Ideally LP within 2 hrs of antibiotic administration
PCR still possible after this
CT SIGNS OF HIGH ICP
Ventricle size
Slit-like or none
Basilar cistern size
Mildly effaced or effaced
Sulci size
Effaced or none visible
Transfalcine herniation (midline shift)
Loss of gray-white matter differentiation

19. Viral meningitis Typical meningitis symptoms
May have viral syndrome OR thunderclap onset
NO altered LoC, seizures or focal neurology
Often appear ‘well’ (but miserable!)
Stable symptom course
85% enterovirus
LP confirms diagnosis
Treatment supportive

20. Encephalitis Viral infection of brain parenchyma
Headache and fever common, but not reliably present.
Meningism mild or absent
Focal neurology signs – higher functions
Due to grey matter inflammation – aphasia, behavior change, lethargy, movement disorder, ‘psychiatric’ phenomenon, memory loss
Seizures/confusion
Varying viral aetiologies
HSV potentially most damaging – 20% mortality 25-40% neurological morbidity

21. Encephalitis Diagnosis made by CSF PCR CTB required before LP
MRI/EEG supportive
LP findings similar to viral meningitis
Treatment: institute early –
Aciclovir 10mg/kg IV tds

22. Temporal arteritis Vasculitis of medium-large arteries
Classic symptoms of headache and temporal artery tenderness. Jaw claudication common.
May only have weakness, lethargy, headaches , +/- fever +/- anaemia
Strongly associated with PMR
Occurs age >50
Only useful investigation ESR > 50
Need to prevent visual loss
If suspected – treat
Prednisone 50mg daily AND
Aspirin 100mg daily
Refer for biopsy and rheumatology f/u

23. Intracranial tumour
Fear of brain tumour far outweighs actual brain tumours in ED presentations
Classic early morning headaches, with positional change not common
Non-specific headache 70% pts
Often few other findings
Suspect with hx of
Vomiting
Neurological changes (often subtle)
Personality changes
New onset seizure (esp. focal)
Background hx Ca.

24. Idiopathic Intracranial Hypertension
Pseudotumor cerebri, Benign intracranial hypertension
Uncommon –younger, overweight, women age 15-50
Persistent headaches, consistent with high ICP
Due to abnormal CSF production/excretion
Papilloedema characteristic feature
Risk of visual field loss
Diagnosed by LP CSF pressure >25 cm
LP therapeutic !
Treat with acetazolamide 250mg bd
Refer for follow up Opthalmology/Neurology review

25. Questions?

26. Summary
Take a good headache history ; ensure to check eyes, temporal arteries on exam
Not everyone needs a scan (but many will get one!) and bloods not usually helpful
Migraine stereotypical; don’t diagnose 1st ever migraine if age>30
CT +/- LP for sudden onset headaches
Don’t delay antimicrobials if meningitis/encephalitis considered likely
Temporal arteritis only occurs age > 50
LP both diagnostic and therapeutic if IIH considered