What Is a Subarachnoid Hemorrhage (Stroke)?

What Is a Subarachnoid Hemorrhage (Stroke)?

A stroke is the interruption of blood flow to part of the brain. A subarachnoid hemorrhage is a type of stroke. A blood vessel on the surface of the brain bursts (hemorrhages). This spills blood into the surrounding tissue. This type of stroke often happens suddenly, with little warning. It is the most serious of all types of strokes. 

Cross section of brain in skull showing burst aneurysm in blood vessel on surface of brain. Vessel is bleeding into space between brain and skull.

During a Subarachnoid Hemorrhage

This type of stroke happens when a major blood vessel bursts on the surface of the brain. Normally, the space between the brain and the skull is filled with a clear fluid. When the blood vessel bursts, blood flows into the space between the brain and the skull. The amount of fluid in this space increases and puts pressure on the brain. This pressure can damage nearby parts of the brain.

Most of these strokes happen when a cerebral aneurysm bursts. An aneurysm is a weak spot in the wall of a blood vessel. A bubble often forms in this weak spot. In some cases, a cerebral aneurysm causes pain or other symptoms. In most cases, though, an aneurysm causes no symptoms until it bursts.

Symptoms of a Subarachnoid Hemorrhage

Any stroke is a medical emergency. If you have any of the following symptoms, even if they seem to get better, call 911 right away:

  • Sudden, excruciating headache

  • Nausea and vomiting (often with headache)

  • Sudden decrease in alertness

  • Trouble moving or loss of feeling

  • Sudden mood changes

  • Sudden dimness, double vision, or loss of vision, particularly in one eye

  • Eyes suddenly very sensitive to light

  • Neck and shoulder pain or stiff neck

  • Seizure

Treating Hemorrhagic Stroke

The acute phase lasts from the first minutes to hours after symptoms begin. During this phase, treatment focuses on relieving pressure on the brain and preventing further damage. A procedure or surgery may be done to repair the burst aneurysm. A drain may be placed into the brain to relieve pressure. Medications to control blood pressure may be given through an IV line. Pain medications can also be given as needed. Tests will likely be done to check for other aneurysms in the brain. If they are found, surgery may be done to reduce the risk that they will burst and bleed.

After the acute phase, treatment focuses on recovery. Long-term damage from a stroke can include paralysis, trouble speaking or understanding, and trouble thinking clearly. Rehabilitation therapy (rehab) can help reduce these effects and regain skills. Rehab begins in the hospital. It then continues in an inpatient or outpatient facility, and eventually at home. It will focus on regaining lost skills. It may include:

  • Help regaining movement.

  • Therapy for speech and language

  • Help with swallowing

  • Help reducing risk factors for another stroke, such as smoking

In addition, medications that help prevent another stroke may be given. These include medications to control blood pressure and prevent bleeding.