SAH

Question 1

Who is most likely to suffer from a SAH?

Answer 1

-Mean age = 50 y/o
-Cause of 6% of strokes, but 1 in 2 mortality rate
-Similar risk factors as for stroke

Question 2

How does a SAH present?

Answer 2

-WORST HEADACHE EVER
-Sudden, explosive headache lasting a few seconds
-Usually accompanied by N+V
-Typically pain pulsates occipitally but can vary
-7% experience seizures
-Neck stiffness / meningism, usually occurs around 6h after onset

Question 3

How would you investigate a SAH?

Answer 3

-CT head (no contrast) - to be performed within 6h of onset hyper dense area of blood in basal cisterns
-If confirmed on CT, origin determined by CT angiography
-If not confirmed on CT but Hx suggests SAH, LP can be performed to look for xanthochromia (12h post onset)
-ECG changes are common, careful not to mistake for an MI

Question 4

How should you manage a SAH?

Answer 4

Early:
-Maintain airway and provide oxygen
-Analgesia (codeine, morphine)
-Antiemetic (promethazine, cyclizine)
Prevent re-bleeding (usually 6 months later):
-Surgical coiling via femoral artery
-Surgical clipping around neck of aneurysm
Ongoing:
-Maintain systolic BP below 180
-Avoid drastic drop in BP to prevent delayed cerebral ischaemia due to vasospasm (self-protection of brain, usually occurs 5-10 days later)
-Calcium antagonists (nimodipine 60mg 4-hourly) prevents this