Subarachnoid hemorrhage in the elderly

Subarachnoid haemorrhage (SAH) is a general term for bleeding blood from various causes into the subarachnoid space. Clinically, it can be divided into two types: spontaneous and traumatic, and spontaneous can be divided into two types: primary and secondary. Pulmonary rupture of blood caused by various reasons into the subarachnoid space is called primary subarachnoid hemorrhage; bleeding from the brain parenchyma penetrates the brain tissue and flows into the subarachnoid space is called secondary subarachnoid hemorrhage . Generally, the so-called subarachnoid hemorrhage refers only to primary subarachnoid hemorrhage, which accounts for about 15% of acute cerebrovascular disease, and those described in this section are also limited to this. The incidence of subarachnoid hemorrhage in the elderly is 21.6% to 39.5%, which is higher than the incidence of 10.5% to 20% in adults, so it needs attention.