Spontaneous Subarachnoid Hemorrhage Flashcards
__-__% of strokes are due to subarachnoid hemorrhage
5-10%
What is the most common cause of subarachnoid hemorrhages?
trauma
A spontaneous subarachnoid hemorrhage result from what 2 things?
- rupture of an arterial saccular (“berry”) aneurysm
- from an arteriovenous malformation
What is it called when small amounts of blood escape the aneurysm a few hours or days before it ruptures?
“warning leaks”
What are the signs of a warning leak?
Headaches sometimes accompanied by nausea and neck stiffness
Describe symptoms during onset
- sudden headache of a severity never experienced previously by the patient
- nausea
- vomiting
- LOC
- nuchal rigidity
Are men or women more at risk for a subarachnoid hemorrhage?
females
What ethnic group is at higher risk?
“nonwhite”
What are 3 other predisposing factors for subarachnoid hemorrhage?
- hypertension
- tobacco smoking
high alcohol consumption (>150g/week)
Are focal neurological signs usually present?
No
When focal neurological signs are present what 2 things that could possibly be the cause?
- a focal intracerebral hematoma
- ischemia in the territory of the vessel with a ruptured aneurysm
What imaging modality should be performed immediately to confirm that hemorrhage has occurred and to search for clues regarding its source?
CT angiography
Why is CT preferred over MRI?
because it is faster and more sensitive in detecting hemorrhage in the first 24 hours
What must be examined in patients that appear normal on CT but are suspected of hemorrhage?
CSF
What are 2 abnormal findings in the CSF that indicate hemorrhage?
- blood
- xanthochromia
