What are the most serious complications following subarachnoid hemorrhage from aneurysm rupture?

What are the most serious complications following subarachnoid hemorrhage from aneurysm rupture?

The most serious sequela of subarachnoid hemorrhage is re-bleeding. The incidence of re-bleeding following aneurysm rupture is approximately 15% in the first week, and approximately 10% in the second week. Morbidity and mortality following re-bleed is very great and has motivated the trend towards early intervention following aneurysm rupture.

Cerebral vasospasm is also a major cause of morbidity and mortality following subarachnoid hemorrhage. Symptomatic brain ischemia from vasospasm occurs in 15–35% of patients. Angiographic evidence of vasospasm occurs in as many as 70% of patients. Vasospasm may lead to cerebral infarction.

Subarachnoid hemorrhage often also leads to hydro-cephalus and may result in dangerously elevated intra-cranial pressure.