Subarachnoid hemorrhage is bleeding in the area between the brain and the thin tissues that cover the brain. This area is called the subarachnoid space.
Hemorrhage – subarachnoid
Causes, incidence, and risk factors
Subarachnoid hemorrhage can be caused by:
Bleeding from an
Bleeding from a
Unknown cause (idiopathic)
Use of blood thinners
Subarachnoid hemorrhage caused by injury is often seen in the elderly who have fallen and hit their head. Among the young, the most common injury leading to subarachnoid hemorrhage is motor vehicle crashes.
Aneurysmin other blood vessels
Fibromuscular dysplasia (FMD) and other connective tissue disorders
High blood pressure
polycystic kidney disease
A strong family history of aneurysms may also increase your risk.
The main symptom is a severe headache that starts suddenly (often called thunderclap headache). It is often worse near the back of the head. Many persons often describe it as the “worst headache ever” and unlike any other type of headache pain. The headache may start after a popping or snapping feeling in the head.
Decreased consciousnessand alertness
Eye discomfort in bright light (
- Mood and personality changes, including
Muscle aches(especially neck painand shoulder pain)
- Nausea and vomiting
- Numbness in part of the body
- Stiff neck
Vision problems, including double vision, blind spots, or temporary vision loss in one eye
Other symptoms that may occur with this disease:
Eyelid drooping Pupil size difference
- Sudden stiffening of back and neck, with arching of the back (
opisthotonos; not very common)
Signs and tests
A physical exam may show a stiff neck
A brain and nervous system exam may show signs of decreased nerve and brain function (focal
An eye exam may show decreased eye movements — a sign of damage to the cranial nerves (in milder cases, no problems may be seen on an eye exam)
If your doctor thinks you have a subarachnoid hemorrhage, a
Other tests that may be done include:
Cerebral angiographyof blood vessels of the brain
CT scan angiography (using contrast dye)
- Transcranial Doppler ultrasound — to look at blood flow in the arteries of the brain
Magnetic resonance imaging (MRI) and
magnetic resonance angiography(MRA) (occasionally)
The goals of treatment are to:
Save your life
Repair the cause of bleeding
Prevent complications such as permanent brain damage (stroke)
Surgery may be done to:
Remove large collections of blood or relieve pressure on the brain if the hemorrhage is due to an injury
Repair the aneurysm if the hemorrhage is due to an aneurysm rupture
If the patient is critically ill, surgery may have to wait until the person is more stable.
Surgery may involve:
Craniotomy(cutting a hole in the skull) and aneurysm clipping — to close the aneurysm
Endovascular coiling— placing coils in the aneurysm and stentsin the blood vessel to cage the coils reduces the risk of further bleeding
If no aneurysm is found, the person should be closely watched by a health care team and may need more imaging tests.
Treatment for coma or decreased alertness includes:
Draining tube placed in the brain to relieve pressure
Methods to protect the airway
A person who is is conscious may need to be on strict bed rest. The person will be told to avoid activities that can increase pressure inside the head, including:
Suddenly changing position
Treatment may also include:
Medicines given through an IV line to control blood pressure
Nimodipine to prevent artery spams
Painkillers and anti-anxiety medications to relieve headache and reduce pressure in the skull
Phenytoin or other medications to prevent or treat seizures
Stool softeners or laxatives to prevent straining during bowel movements
How well a patient with subarachnoid hemorrhage does depends on a number of different factors, including:
Location and amount of bleeding
Older age and more severe symptoms can lead to a poorer outcome.
People can recover completely after treatment. But some people die even with treatment.
Repeated bleeding is the most serious complication. If a cerebral aneurysm bleeds for a second time, the outlook is much worse.
Changes in consciousness and alertness due to a subarachnoid hemorrhage may become worse and lead to
Other complications include:
Complications of surgery
Medication side effects
Calling your health care provider
Go to the emergency room or call the local emergency number (such as 911) if you have symptoms of a subarachnoid hemorrhage.
Identifying and successfully treating an aneurysm can prevent subarachnoid hemorrhage.
Related:Headache – what to ask your doctor , Aneurysm in the brain, Arteriovenous malformation – cerebral, Aneurysm, Polycystic kidney disease, Stroke