OSCE rev

Question 1

What red flags to run out in headache hx?

Answer 1

Focal neurology- double vision?, loss of vision?, any vertigo?, problems with balance?, any weakness in your limbs? any changes to sensation- tingling/burning)?, problems with talking/slurred speech, difficulty swallowing ?
Thunderclap- sudden? severe? did it get severe very quickly?
Meningism- any neckstiffness, difficult looking at bright lights ?
Any fever?- infection (meningitsi)
Any rashes?- check if non blanching
Raised ICP- worse in morning, worse with bending/lying down, coughing, N+V, papillodema, diplopia, confusion
Any hx of malignancy?
Temporal arteritis- jaw claudication, scalp tenderness

Question 2

How percentage of subarachnoid haemorrhages will be seen on non contrast CT scans and what occurs if its delayed ?

Answer 2

90% sensitivity in 24 hrs
50% sensitivity in 72 hrs

Question 3

If the CT scan does not show fresh blood what would you do depending on the time since symptom onset?
<6 hrs
>6 hrs

Answer 3

• if CT head is done within 6 hours of symptom onset and is normal
  new guidelines suggest not doing a lumbar puncture
  consider an alternative diagnosis
• if CT head is done more than 6 hours do a lumber puncture (LP)
  (LP should be performed at least 12 hours following the onset of symptoms to allow the development of xanthochromia)
  xanthochromia helps to distinguish true SAH from a ‘traumatic tap’ (blood introduced by the LP procedure).
  as well as xanthochromia, CSF findings consistent with subarachnoid haemorrhage include a normal or raised opening pressure