Subarachnoid Hemorrhage

Subarachnoid hemorrhage is bleeding into the space around the brain, and it is a medical emergency. The most typical symptom is a very severe headache that starts suddenly; nausea, vomiting, neck stiffness, visual changes, or impaired consciousness may also accompany it.

What is subarachnoid hemorrhage?

Subarachnoid hemorrhage is a serious brain bleed caused by accumulation of blood in the subarachnoid space between the surface of the brain and the membranes surrounding it. One of the most common causes is rupture of a brain aneurysm, although other causes such as head trauma can also play a role. This condition may begin with a sudden, very severe headache and can rapidly lead to life-threatening complications. For that reason, emergency evaluation is necessary even if the intensity of the headache later decreases. ^[1][2]

What are the symptoms?

The most typical sign is a headache that begins suddenly and becomes extremely severe within seconds. Some people describe it as “the worst headache of my life.” Nausea, vomiting, neck stiffness, light sensitivity, confusion, double vision, seizures, and brief loss of consciousness may occur. Not every sudden severe headache is a subarachnoid hemorrhage, but this kind of headache must be evaluated urgently. ^[1][3]

Causes and risk factors

Aneurysm rupture is one of the most important causes. High blood pressure, smoking, certain vascular diseases, and a family history of aneurysm can increase risk. Trauma can also cause subarachnoid hemorrhage. Sometimes there is no previously known vascular problem and the event occurs unexpectedly. ^[1][2][3]

How is it diagnosed?

In the emergency department, brain CT is usually the first imaging test. Vascular imaging and additional neurological evaluation may also be performed when necessary. The goal is to confirm the bleeding, identify the cause, and detect a vascular problem such as an aneurysm. Early diagnosis is important both for management of the hemorrhage and for reducing the risk of rebleeding. ^[2][4]

How is it treated?

Treatment begins under intensive care conditions with stabilization, blood pressure and breathing support, pain control, and management of complications. If an aneurysm is identified, options such as surgical clipping or endovascular treatment may be considered. Close monitoring is also required for complications such as vasospasm, rebleeding, and hydrocephalus. ^[2][4]

Complications and follow-up

Subarachnoid hemorrhage may be complicated by vasospasm, rebleeding, impaired consciousness, seizures, hydrocephalus, and permanent neurological effects. For that reason, follow-up by neurology or neurosurgery, rehabilitation, and risk-factor management remain important even after hospital discharge. ^[2][4]

When is emergency help needed?

Emergency help should be called immediately for a suddenly occurring, extremely severe headache, loss of consciousness, seizure, a new neurological deficit, or worsening after a serious head injury. Waiting is not safe. ^[1][2]

Brief conclusion

Although rare, subarachnoid hemorrhage is a serious brain bleed that requires urgent diagnosis. A sudden, unusually severe headache should always be treated as a medical emergency. ^[1][2]

For safe assessment, symptoms should be considered together with personal risk factors; particularly if emergency warning signs are present, individualized medical evaluation should not be delayed. ^[1][2]