Neurological Emergencies Flashcards
To Do: Status Epilepticus Subarachnoid Haemorrhage Meningitis Other... Done:
A patient presents to A and E with “the worst headache of ther life”. They have associated N and V.
What is the main differential diagnosis,
and what is the cause in 70% of these cases?
Subarachnoid haemorrhage
Berry auneurysms
A patient presents to A and E with “the worst headache of ther life”. They have associated N and V.
What is the main differential diagnosis,
and what is the cause in 15% of these cases?
Subarachnoid haemorrhage
AV malformations
A patient presents to A and E with “the worst headache of ther life”. They have associated N and V.
How might this condition have presented in a less fortunate patient?
Coma
Seizures
Sudden death
Why do some patients with a SAH get meningism?
Blood acts as an irritant -> chemical meningitis
A patient presents to A and E with “the worst headache of ther life”. They have associated N and V.
What signs might you elicit O/E?
Kernig's sign Signs of meningism Impaired consciousness Cranial nerve palsys Hemiplegia
With a SAH, how quickly can CNS deficits become permenant?
Within minutes
What is the overall mortality for a patient with an SAH?
35-50%
Is prognosis with an SAH better or worse with an aneurysm than an AVM?
Worst with aneurysm, better with AVM, best with no lesion detected.
Why is blood in the subarachnoid space bad?
It acts as an irritant causing vasospasm -> ischaemia -> secondary brain damage.
How common is rebleeding following a SAH?
Very - usually ocurs within 7 days.
How do we investigate suspected SAH?
CT ASAP if within the first 12 hours.
LP 12 hours after the event.
Check clotting screen.
How good are CT scans for picking up subarachnoid haemorrhages?
95% can be picked up if done within 24 hours, but CT shows fresh blood up best so ideally do ASAP for clearest diagnosis.
What does a subarachnoid haemorrhage look like on CT?
No characteristic shape - just an area of hyperdensity.
Why do we do an LP 12 hours after a SAH, and what can it tell us?
To look for RBCs and xanthochromia in the CSF.
We do it after 12 hours so the SAH blood has time to break down and form the xanthochromia, so SAH isn’t confused with RBCs from the trauma of LP procedure.
It tells us if there has been a SAH.
What do we send off the CSF for when we do an LP for ?SAH?
Xanthochromia
MC&S
Glucose
Protein
Might as well screen for infection while we are in there!
A pt presents to A&E with a thunderclap headache. SAH has been confirmed.
How should we manage this patient?
Initially with ABCDE.
Stabilise
Prevent rebleed
Treat vasospasm
Correct any biochemical abnormalities e.g. hyponatraemia
Refer for neurosurgical intervention.
Why is it important to manage cerebral vasospasm in a SAH pt?
It causes focal cerebral ischaemia -> death.
How do we try and prevent cerebral vasospasm post-SAH?
Hydration with normal saline -> hypervolaemia and haemodilution
Nimodipine 60mg 4 hourly
Re-examine regularly for changes in function.
What is nimodipine?
A calcium antagonist used to prevent vasospasm post-SAH.
What neurosurgical interventions are possible for SAH?
Clipping or endovascular coiling of aneurysm depending on pt, site and size of aneurysm, and comorbidities.
A pt comes in with a thunderclap headache, and SAH is diagnosed.
After initial management, the pt appears stable, but after admission for observation, he suddenly becomes drowsy and his GCS drops.
What should we do?
Get an urgent CT head as he might have a re-bleed or hydrocephalus.
A pt comes in with a thunderclap headache, and SAH is diagnosed.
After initial management, the pt appears stable, but after admission for observation, he suddenly becomes drowsy and his GCS drops.
Other than drowsiness/drop in GCS, what other indications are there for urgent CT post SAH?
Seizures
Focal neurological deficit (new)
Coma
Cognitive decline (acute)
Need to check for a re-bleed or hydrocephalus!!
What are the common complications associated with SAH?
Re-bleeding Hydrocephalus Cerebral ischaemia Hyponatraemia Headaches Hypopituitarism
Death
A pt is brought to A&E by their partner, because they were complaining of a headache when they woke up this morning, and since then they have become drowsy and aren’t responding appropriately or at all to stimulus.
What are we most worried about here, and what could cause this?
RICP
Head injury Intracranial tumour Intracranial bleed Infection (meningitis, encephalitis, abscess) Hydrocephalus Cerebral oedema