St Emlyn’s Lesson Plans
Headache: the history that changes the plan
Use onset and associated symptoms to discuss investigation of sudden headache and urgent care for possible giant cell arteritis.
New to Emergency Medicine / Induction / Early-career Emergency Medicine · 45-minute session
For learners
Before: Allow about 15 minutes in total.
When we meet: We will discuss the timing of CT and lumbar puncture, then a new headache with visual symptoms in an older patient.
For facilitators
Send: the learner preparation link before teaching.
Bring: Whiteboard or paper timeline. The two negative CT results and their timings are supplied in case one; no separate reports or images are needed.
Before the session
If you are attending this session, complete the core preparation below before you come. Allow about 15 minutes in total.
Core preparation
NICE NG228: Subarachnoid haemorrhage · About 8 minutes
Read NG228’s assessment and diagnostic recommendations. Focus on time from symptom onset, CT reporting and when lumbar puncture is considered.
https://www.nice.org.uk/guidance/ng228/chapter/Recommendations
BSR: Diagnosis and treatment of giant cell arteritis · About 4 minutes
Read the society’s explanation of giant cell arteritis, including visual symptoms and why urgent assessment matters.
https://www.rheumatology.org.uk/news/details/articleid/217
Think about (allow 3 minutes): How would a negative CT at four hours change the discussion compared with one at fourteen hours?
Picture the scene
The triage note says “headache, different from usual migraine”. What is different, and how quickly did it begin?
By the end of the session
- Elicit onset and associated features that change the differential diagnosis.
- Explain the current CT/lumbar-puncture pathway for suspected subarachnoid haemorrhage.
- Recognise when possible giant cell arteritis requires urgent treatment and specialist assessment.
After the session
- Document the time to maximum intensity explicitly in your next headache history.
- Check that your discharge explanation identifies what has and has not been excluded.
Optional further learning
You do not need to complete this before attending. The listening time is additional to the core preparation above.
Optional listening · 41 min 22 sec
St Emlyn’s Podcast: Ep 243 - The Subarachnoid Haemorrhage in Emergency Department (SHED) Study
Explore how research changes our understanding of residual risk after a negative CT.
Search for this episode by title in MedPod Learn if you want to record your listening there.
For an advanced discussion, compare SHED’s selected cohort, CT timing and follow-up with current NICE NG228. Low residual risk does not guarantee exclusion in every patient. Retain the six-hour distinction and consider LP after a negative later CT. Allow 41 minutes for this optional research discussion.
https://www.stemlynspodcast.org/e/ep-243-the-subarachnoid-in-emergency-department-shed-study/
Facilitator guide
Send learners the preparation link several days before teaching. Allow about 15 minutes in total.
Before learners arrive
- Confirm CT-reporting, LP and specialist advice arrangements.
- Check the GCA fast-track and visual-symptom pathway, including current steroid prescribing instructions.
- Prepare a simple onset-to-investigation timeline.
Equipment: Whiteboard or paper timeline. The two negative CT results and their timings are supplied in case one; no separate reports or images are needed.
Setup: Draw the onset-to-investigation timeline together. Give one pair the early CT result and another the late result, then compare their explanations. Use the GCA case to discuss action while confirmation is arranged.
If the preparation has not been completed
Replace the opening question and timeline activities (12 minutes). With the linked NG228 diagnostic recommendations open, spend eight minutes drawing symptom onset, CT and possible LP on a whiteboard. Use four minutes to compare the two CT timings supplied in case one; no additional reports are needed. For the 30-minute version, use the first eight minutes for a five-minute shared timeline and three-minute comparison, replacing the onset question and timeline activities.
Suggested session plan
- 0–5 min — Ask a better opening question. Compare “how bad?” with “how did it start?”.
- 5–12 min — Place the tests on a timeline. Groups locate onset, CT and possible LP.
- 12–35 min — Discuss both cases. Spend most time explaining what a negative test does and does not establish.
- 35–40 min — Consolidate. Pairs justify the next step for early and late CT.
- 40–45 min — Choose a follow-up action. Choose a more precise onset question for the next shift.
Start the discussion
Read the opening scenario together. Give everyone a moment to think, then ask what concerns them and what they need to know next.
Cases and discussion
Use these cases, or invite an anonymised case from the group that addresses the same questions.
The clock starts at symptom onset
A 59-year-old develops a sudden severe occipital headache, reaching its maximum within minutes. Examination is currently normal.
Add this information as the discussion develops:
- Scenario A: a non-contrast CT obtained four hours after onset is reported negative by a radiologist.
- Scenario B: the same scan is performed fourteen hours after onset.
Ask the group:
- Which history details make this urgent?
- How do the two scan timings change the next discussion?
- What diagnoses remain possible after a negative scan?
Discussion notes
Points to draw out:
- Establish a careful onset timeline and consider SAH despite a normal neurological examination; obtain senior review and urgent investigation.
- NG228 says not to routinely offer LP after a negative CT within six hours reported by a radiologist; seek specialist advice and consider other diagnoses.
- For a negative CT after six hours, consider LP; when indicated, wait at least twelve hours from onset. Explain benefit, limits and the local pathway.
- A negative SAH investigation is not a universal exclusion of secondary headache.
Common misconceptions:
- Using pain severity or location alone to rule SAH in or out.
- Measuring six hours from ED arrival rather than onset.
For a more experienced group: Discuss an unreliable onset history, an uncertain report or persistent clinical concern with radiology/specialist input.
A new headache with visual symptoms
A 68-year-old has new temporal headache, jaw discomfort while chewing and a brief episode of altered vision.
Add this information as the discussion develops:
- Inflammatory markers are not markedly raised.
Ask the group:
- What must not wait for a biopsy or scan?
- Who needs to assess the patient urgently?
- What would you say about uncertainty?
Discussion notes
Points to draw out:
- Suspected GCA with visual symptoms is urgent: involve senior clinicians and ophthalmology/rheumatology via the local fast-track pathway.
- Strong clinical suspicion should prompt treatment according to that pathway rather than waiting for confirmatory testing.
- Normal or modest inflammatory markers do not settle the diagnosis. Document symptoms and vision, and organise definitive assessment.
Common misconceptions:
- Treating inflammatory markers as a stand-alone exclusion test.
- Using an unverified steroid regimen instead of the current local GCA pathway.
For a more experienced group: Consider other secondary causes in an older patient; keep the pathway focused on the actual clinical findings.
Important clinical points
- Do not delay emergency assessment of sudden severe headache because the neurological examination is normal.
- Use the current local GCA prescribing pathway with urgent specialist input, especially for visual symptoms.
- Sepsis/meningitis and other time-critical causes require their own assessment and treatment.
Closing the session
Use these questions to check what the group will take away. Go back over any clinical points that remain unclear.
- What does a negative CT at four hours mean that a negative CT at fourteen hours does not?
- What would you do if onset time is uncertain?
- Why can suspected GCA require treatment before confirmation?
Key teaching points:
- Establish how the headache began and how quickly it reached maximum intensity.
- Interpret a negative CT in relation to timing, reporting and the remaining clinical concern.
- Possible GCA with visual symptoms needs urgent assessment and treatment through the local pathway.
Before leaving, ask each person to choose one action from After the session and say when they will try it. They complete that follow-up in practice, with supervision where needed.
Adapting the discussion
Uncertainty and local practice
Early negative CT does not remove the need for judgement about report quality, onset uncertainty and alternative diagnoses. Use specialist advice where concern persists.
If the discussion drifts
Which part of the history or test changes what we do next?
For a more experienced group
Add pregnancy/postpartum headache, anticoagulation, immunosuppression or suspected cerebral venous thrombosis and identify why the SAH pathway alone is insufficient.
A 30-minute version
30 minutes: onset question 3; timeline 5; SAH case 12; GCA case 7; reflection 3. Omit the extended alternative-diagnosis round.
Evidence and guidance
- NICE NG228: Subarachnoid haemorrhage — CT timing/reporting and when to consider lumbar puncture.https://www.nice.org.uk/guidance/ng228/chapter/Recommendations
- NICE NG228: Diagnostic rationale — Explains the six-hour CT and twelve-hour lumbar-puncture intervals.https://www.nice.org.uk/guidance/ng228/chapter/Rationale-and-impact
- BSR: Diagnosis and treatment of giant cell arteritis — Society explanation linking its 2020 guideline; suspected GCA needs urgent treatment and specialist assessment.https://www.rheumatology.org.uk/news/details/articleid/217
Suggested curriculum links
RCEM 2021 curriculum (2025 update): SLO1 Care for physiologically stable adults with acute presentations
Safe assessment, differential diagnosis and disposition.
Check these links against the learner’s stage and programme. Attendance at a teaching session does not establish competence.
First published 2020-06-08 · Iain Beardsell.