Is a Subarachnoid Hemorrhage?
Subarachnoid hemorrhage (SAH) refers to bleeding within the
subarachnoid space, which is the area between the brain and the tissues that
cover the brain.
The subarachnoid space is the space where the cerebrospinal fluid
circulates, and it’s responsible for protecting your brain from serious
injuries by serving as a cushion. A hemorrhage in this space can cause a coma,
paralysis, and even death.
This condition can occur quickly, and the key to survival is
immediate medical intervention. Call a doctor or 911 as soon as possible if you
or someone you know has the symptoms of SAH.
This life-threatening condition is also rare. According to the Brain Aneurysm Foundation, SAH
accounts for between 0.01 and 0.08 percent of visits to the emergency room.
When SAH develops, it has several symptoms. The main symptom is a
sudden, severe headache, which is more intense at the base of the skull. Some people
may even feel a popping sensation in their head before the hemorrhage begins.
You may also have:
- neck pain
- numbness throughout your body
- shoulder pain
- sensitivity to light
- decreased vision
- rapid loss of alertness
The symptoms of SAH come on suddenly, and you may lose
consciousness quickly. You should get emergency medical attention right away if
you experience any of these symptoms combined with a severe headache,
SAH is often related to brain aneurysms, which are abnormalities
within the brain’s arteries. The most common cause of primary SAH is a
congenital berry aneurysm. It’s called a berry aneurysm because it forms a
cluster of sac-like pouches in a cerebral vessel that looks like a cluster of
berries. These aneurysms swell up and weaken the walls of the arteries over
When an aneurysm erupts, it quickly bleeds and forms a clot. This
condition is responsible for most SAH cases. Aneurysmal hemorrhage may occur at
any age, but it’s most common from age
40 to 65. In some cases, trauma to the brain during an injury can cause
aneurysms and result in a subarachnoid hemorrhage.
Other causes of SAH include:
- bleeding from an arteriovenous malformation
- bleeding disorders
- use of blood thinners
A serious head injury, such as one that occurs in a car crash or
when an older person falls and hits their head, can also lead to an SAH.
Factors for SAH
SAH can occur at any age, and some people are even born with
cerebral aneurysms that can lead to this condition. According to the Internet
Stroke Center, women are more likely to develop SAH than men.
One in 50 people is
estimated to have an unruptured aneurysm in the United States. You should talk
to your doctor about your risk of developing an aneurysm if you have a history
of brain aneurysms
If you have aneurysms, it’s important to see your doctor
regularly to help figure out your potential for hemorrhaging before SAH
SAH is often detected during a physical exam. Your doctor may
notice that you have a stiff neck and vision problems. This combination often
leads to a diagnosis of SAH. You’ll need more testing to find out the severity
of the hemorrhage so that you can get proper treatment.
First, your doctor may conduct a CT scan of the head to look for
bleeding in your skull. If the results are inconclusive, the doctor may use a
contrast dye during the procedure.
Other tests include:
- an MRI scan, which uses radio waves to get clear,
detailed images of the brain
- a cerebral angiography, which uses an X-ray and
injected dye to detect blood flow in the brain
- a transcranial ultrasound, which detects blood
flow in the arteries within the brain
This condition is often misdiagnosed because 73 percent of people don’t get
Rapid treatment is important to save your life and reduce the
possibility of brain damage. Surgery is performed to first clip, or close, the
aneurysm and stop future bleeding. It’s then done to more permanently repair the
If your aneurysm is being clipped, a craniotomy is performed and
the aneurysm is closed. A craniotomy involves opening the skull to expose the
area of involvement. A technique called endovascular coiling may also be used
to reduce the risk of further bleeding.
If SAH causes a coma, treatment will include appropriate life
support with artificial ventilation, protection of the airways, and placement
of a draining tube in the brain to relieve pressure.
If you don’t lose consciousness from the SAH, you’ll still be
given strict instructions to prevent post-treatment coma. Bed rest is standard
for people recovering from this condition. Your doctor will also ask you to
refrain from straining your body or bending over. These actions can increase
the pressure on your brain.
Your doctor may prescribe medications to:
- prevent seizures with phenytoin or other
- regulate blood pressure with medication through
- prevent artery spasms with nimodipine
- relieve severe headaches with painkillers and
Are the Complications of SAH?
Even after SAH treatment, you may be at risk for related
complications. The most common complication is called repeated bleeding. This
happens when a rupture that has healed itself ruptures again. Repeated bleeding
your risk of death. Comas due to SAH can also eventually lead to death.
In some cases, people may experience seizures or strokes
Can I Prevent SAH?
The only way to prevent this condition is to identify potential
problems within the brain. Early detection and, in some cases, treatment of a
brain aneurysm can prevent a subsequent hemorrhage in the subarachnoid space.
Is the Long-Term Outlook for SAH?
SAH is a serious condition that can be fatal. The recovery period
is long, and you may be at a higher risk of complications if you’re older or
have poor overall health.
Treatment isn’t a guarantee. Some people die even after the most
aggressive medical interventions. The earlier you seek emergency medical care,
the better your chances of survival.