Subarachnoid Hemorrhage

A subarachnoid hemorrhage (SAH) is a life-threatening type of stroke that occurs when there is bleeding into the space surrounding the brain, known as the subarachnoid space. This space contains cerebrospinal fluid (CSF), which cushions and protects the brain.

Causes

The most common cause of SAH is the rupture of an aneurysm in the brain. An aneurysm is a weak or thin spot on an artery wall that can balloon out and eventually burst, leading to bleeding into the subarachnoid space. Other causes of SAH include:

• Arteriovenous malformations (AVMs): abnormal connections between arteries and veins
• Trauma: head injuries that cause blood vessels to rupture
• Blood vessel disorders: such as moyamoya disease or vasculitis
• Bleeding disorders: such as hemophilia or sickle cell disease
• Tumors: rare cases of brain tumors that bleed into the subarachnoid space

Symptoms

The symptoms of SAH can vary depending on the severity and location of the bleeding. Common symptoms include:

• Sudden and severe headache, often described as "the worst headache of my life"
• Nausea and vomiting
• Confusion and disorientation
• Seizures
• Weakness or numbness in the face, arm, or leg
• Difficulty speaking or understanding speech
• Loss of consciousness

Diagnosis

SAH is typically diagnosed using a combination of the following tests:

• Computed Tomography (CT) scan: to visualize the brain and detect bleeding
• Magnetic Resonance Imaging (MRI): to provide more detailed images of the brain and blood vessels
• Lumbar puncture (LP): to collect CSF and check for blood or other abnormalities
• Angiography: to visualize the blood vessels and detect aneurysms or AVMs

Treatment

The treatment of SAH depends on the underlying cause and severity of the bleeding. Common treatments include:

• Surgical clipping or coiling of aneurysms: to prevent further bleeding
• Endovascular embolization: to block blood flow to AVMs or aneurysms
• Medications: to control blood pressure, prevent seizures, and manage pain
• Intensive care unit (ICU) monitoring: to closely monitor the patient's condition and provide supportive care

Complications

SAH can lead to several complications, including:

• Vasospasm: narrowing of blood vessels that can reduce blood flow to the brain
• Hydrocephalus: accumulation of CSF in the brain that can increase pressure
• Rebleeding: further bleeding from the same or another aneurysm or AVM
• Brain injury: damage to brain tissue due to lack of oxygen or blood flow

Prognosis

The prognosis for SAH varies depending on the severity and location of the bleeding, as well as the patient's overall health. With prompt medical attention and treatment, some patients can make a full recovery, while others may experience long-term disability or death.