Subarachnoid haemorrhage Pathology

• In 15% no cause is found; of the remainder, 80% are due to a ruptured aneurysm, 5% to arteriovenous malformations and 15% follow trauma.

• The anterior part of the Circle of Willis is affected in 85-90% of caseswhile 10-15% affect the vertebrobasilar system.

• There is a 30% risk of rebleeding for which the mortality is 40%. Those surviving a month have a 90% chance of surviving a year.

• Cerebral vasospasm occurs in 40-70% of patients at 4-12 days after the bleed. This is the most important cause of morbidity and mortality.

• Hydrocephalus, seizures, hyponatraemia and inappropriate ADH secretion are recognised complications.

0 0

Post a comment