Traumatic (SAH) develops from traumatic brain injury and usually considered a separate disorder known astraumatic brain injury.
Etiology- Spontaneous SAH occurs when an abnormal artery or vein ruptures and blood spills into the subarachnoid space ventricles. In adults, aneurysms are the most common cause of SAH.
An aneurysm is an abnormal bulge or ballooning in the wall of a blood vessel. An aneurysm can burst (rupture), causing internal bleeding and often leading to death. The early precursors of aneurysms are small outpouchings through defects in the media of the arteries.
There is a clear female preponderance overall; SAH is ~1.6 times higher in female than male.
Before age 40 female=male; after age 40 there is an increasingly strong predominance of females.
Hunt and Hess grading system of SAH
Grade 1 - Asymptomatic or mild headache
Grade 2 - Moderate-to-severe headache, nuchal rigidity, andno neurological deficit other than possible cranial nerve palsy
Grade 3 - Mild alteration in mental status (confusion, lethargy), mild focal neurological deficit
Grade 4 - Stupor and/or hemi paresis
Grade 5 - Comatose and/or decerebrate
What are the risk factors of SAH:
*Acquired: Smoking, alcohol, hypertension,.
*Inherited: Platelet glycoprotein polymorphism, Elastin deficiency (chromosome 7qdeficiency), chromosomal deletions
Subarachnoid hemorrhage
