- When an aneurysm ruptures:
- Blood pushes into the subarachnoid space at arterial pressure
- Intracranial pressure equalizes across the rupture site and stops the bleeding
- Thrombus formation at the bleeding site.
- Physical damage due to bleeding and mass effect
- Early brain injury occurs due to:
- Raised intracranial pressure
- Decreased cerebral blood flow
- Complex pathological process ensues characterised by:
- Microthrombosis, oedema, blood-brain-barrier disruption and inflammation
- Results in apoptosis, necrosis and cell death
- Leads to global cerebral ischaemia and infarction
- Sympathetic activation produces systemic manifestations
