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Alternative Names
Brain bleeding; Brain hemorrhage; Stroke - hemorrhagicDefinition Return to top
Hemorrhagic stroke involves bleeding within the brain, which damages nearby brain tissue. See also:
Causes Return to top
Hemorrhagic stroke occurs when a blood vessel bursts inside the brain. The brain is very sensitive to bleeding and damage can occur very rapidly, either because of the presence of the blood itself, or because the fluid increases pressure on the brain and harms it by pressing it against the skull.
Bleeding irritates the brain tissue, causing swelling. The surrounding tissues of the brain resist the expansion of the bleeding, which is finally contained by forming a mass (hematoma). Both swelling and hematoma will compress and displace normal brain tissue.
Most often, hemorrhagic stroke is associated with high blood pressure, which stresses the artery walls until they break.
Another cause of hemorrhagic stroke is an aneurysm. This is a weak spot in an artery wall, which balloons out because of the pressure of the blood circulating inside the affected artery. Eventually, it can burst and cause serious harm. The larger the aneurysm is, the more likely it is to burst. It is unclear why people develop aneurysms, but genes may play a role, since aneurysms run in families.
Stroke can also be caused by the accumulation of a protein called amyloid within the artery walls, particularly in the elderly. This makes the arteries more prone to bleeding.
Amyloid protein is also implicated in the brain damage related to Alzheimer's disease, but the difference is that people with Alzheimer´s disease have amyloid accumulation in the brain tissue instead of in the arteries. Therefore people with Alzheimer´s usually do not develop brain bleeding.
Some people with brain hemorrhage have abnormal connections between arteries and veins. Under normal circumstances, circulating blood travels through the arteries into the capillaries, where it provides nutrients and oxygen to the tissues. Once the blood has deposited the nutrients and oxygen, it is carried back to the heart from the capillaries via the veins.
In some people, however, a brain artery may connect directly to a vein, instead of going through the capillaries first. This is called an arterial-venous malformation (AVM). Since blood pressure in the arteries is much greater than in the veins, the veins may rupture, causing bleeding into the brain.
Another important brain disease that can cause bleeding is cancer. This is especially true for cancers that spread to the brain from distant organs, such as the breast, skin, and thyroid.
About 20% of strokes are hemorrhagic -- but the other 80% are caused by the opposite problem: too little blood reaching an area of the brain, which is usually due to a clot that has blocked a blood vessel. This is called "ischemic stroke." This type of stroke can sometimes lead to a brain hemorrhage because the affected brain tissue softens and this can lead to breaking down of small blood vessels.
In addition, brain hemorrhage can occur when people have problems forming blood clots. Clots, which are the body's way of stopping any bleeding, are formed by proteins called coagulation factors and by sticky blood cells called platelets. Whenever the coagulation factors or platelets do not work well or are insufficient in quantity, people may develop a tendency to bleed excessively.
Some medications (often used, ironically, to prevent ischemic stroke) prevent clot formation. These work by blocking the production of clotting factors (such as the blood thinner warfarin) or interfering with the function of platelets (such as aspirin). The most common side effects of such medications is bleeding, which may occasionally affect the brain. Controlling bleeding to avoid stroke is a very fine balancing act.
Illicit drugs, such as cocaine, can also cause hemorrhagic stroke.
Symptoms Return to top
Stroke symptoms are typically of sudden onset and may quickly become worse. The following is a list of possible problems:
Exams and Tests Return to top
A neurologic exam is almost always abnormal. The patient may look drowsy and confused. An eye examination may show abnormal eye movements, and changes may be seen upon retinal examination (examination of the back of the eye with an instrument called ophthalmoscope). The patient may have abnormal reflexes. However, these findings are not specific to brain hemorrhage.
The most important test to confirm the presence of a brain hemorrhage is a CT scan, which provides pictures of the brain. A CT scan should be obtained without delay. A brain magnetic resonance imaging (MRI) scan can also be obtained later to better understand what caused the bleeding. A conventional angiography (x-ray of the arteries using dye) may be required to identify aneurysms or AVM.
Other tests may include:
Treatment Return to top
Treatment includes life-saving measures, relieving symptoms, repairing the cause of the bleeding, preventing complications, and starting rehabilitation as soon as possible. Recovery may occur over time as other areas of the brain take over functioning for the damaged areas.
IMMEDIATE TREATMENT
Treatment is ideally administered in an intensive care unit, where complications can immediately be detected. Medical personnel pay careful attention to breathing because sometimes persons with brain hemorrhage develop very irregular breathing patterns or even stop breathing entirely.
A person having a hemorrhagic stroke may be unable to protect the airway during coughing or sneezing because of impaired consciousness. Saliva or other secretions may go "down the wrong pipe," which is potentially serious and may cause lung problems such as aspiration pneumonia. To treat or prevent these breathing problems, a tube may need to be placed through the mouth into the trachea to start mechanical ventilation.
The blood pressure may be too high or too low in patients with brain hemorrhage. These problems need to be addressed immediately by doctors. In addition, brain bleeding may cause swelling of surrounding brain tissue, and this may require therapy with some drugs called hyperosmotic agents (mannitol, glycerol, and hypertonic saline solutions).
Bedrest may be advised to avoid increasing the pressure in the head (intracranial pressure). This may include avoiding activities such as bending over, lying flat, sudden position changes or similar activities. Stool softeners or laxatives may prevent straining during bowel movements (straining also causes increased intracranial pressure).
Medications may relieve headache but should be used with caution because they may reduce consciousness. This may produce the wrong impression that the patient is getting worse. Antihypertensive medications may be prescribed to moderately reduce high blood pressure. Medications such as phenytoin may be needed to prevent or treat seizures.
Nutrients and fluids may need to be supplemented if swallowing difficulties are present. This can be intravenous or through a feeding tube into the stomach (gastrostomy tube). Swallowing difficulties may be temporary or permanent.
Positioning, range-of-motion exercises, speech therapy, occupational therapy, physical therapy, and other interventions may be advised to prevent complications and promote maximum recovery of function.
SURGERY
Sometimes, surgery is needed to save the patient's life or to improve the chances of recovery. The type of surgery depends upon the specific cause of brain bleeding. For example, a hemorrhage due to an aneurysm requires special treatment (see aneurysm).
For other types of bleeding, removal of the hematoma may occasionally be needed, especially when bleeding occurs in the back of the brain. Some physicians are currently investigating whether the injection of a "clot buster" inside the hematoma can facilitate the removal of brain hemorrhages through needles or catheters, allowing less invasive surgery.
One common problem related to brain bleeding is hydrocephalus, which is the accumulation of a water-like fluid within the brain cavities called ventricles. To solve this problem, the fluid may need to be drained with a special procedure called ventriculostomy.
For AVM, different treatments are available, including surgical removal of the AVM network, radiosurgery (using ionizing radiation to reduce the size of the AVM), and intra-arterial embolization (a procedure in which glue is injected into the AVM to close the connection between arteries and veins).
LONG-TERM TREATMENT
Recovery time and the need for long-term treatment are highly variable in each case. Physical therapy may benefit some patients. Activity should be encouraged within the person's physical limitations. Alternative forms of communication such as pictures, verbal cues, demonstration or others may be needed depending on the type and extent of language deficit. Speech therapy, occupational therapy, or other interventions may increase the ability to function.
Urinary catheterization or bladder or bowel control programs may be required to control incontinence.
A safe environment must be considered. Some people with stroke appear to have no awareness of their surroundings on the affected side. Others show a marked indifference or lack of judgment, which increases the need for safety precautions.
In-home care, boarding homes, adult day care, or convalescent homes may be required to provide a safe environment, control aggressive or agitated behavior, and meet physiologic needs.
Behavior modification may be helpful for some patients in controlling unacceptable or dangerous behaviors. This consists of rewarding appropriate or positive behaviors and ignoring inappropriate behaviors (within the bounds of safety). Reality orientation, with repeated reinforcement of environmental and other cues, may help reduce disorientation.
Family counseling may help in coping with the changes required for home care. Visiting nurses or aides, volunteer services, homemakers, adult protective services, and other community resources may be helpful.
Legal advice may also be appropriate early in the course of the disorder. Advance directives, power of attorney, and other legal actions may make it easier to make ethical decisions regarding the care of the person with hemorrhagic stroke.
Outlook (Prognosis) Return to top
Stroke is the third leading cause of death in developed countries. About one-forth of people who have a stroke die as a result of the stroke or its complications, about one-half have long-term disabilities, and about one-forth recover most or all function.
Hemorrhagic stroke is less common but more frequently fatal than ischemic stroke.
Possible Complications Return to top
When to Contact a Medical Professional Return to top
Go to the emergency room or call the local emergency number (such as 911) if symptoms of stroke occur. A stroke is a "brain attack," and minutes can make a huge difference in disability and death rates.
Emergency symptoms include seizures or breathing difficulties, loss of consciousness, sudden difficulties with movement or sensation, eating or swallowing difficulties, sudden vision change or loss of vision in one or both eyes, rapid onset of speech changes, and sudden (severe) headache.
Call your health care provider if the condition of a family member with stroke deteriorates to the point that the person cannot be cared for at home.
Prevention Return to top
Most cases of hemorrhagic stroke are associated with specific risk factors, such as high blood pressure, smoking, or cocaine use. Controlling blood pressure and avoiding smoking and cocaine can reduce the chances of brain bleeding. Surgery to correct blood vessel abnormalities like aneurysms or AVMs is sometimes advisable to prevent bleeding.
Update Date: 9/10/2006 Updated by: Daniel Kantor, MD, Director of the Comprehensive MS Center, Neuroscience Institute, University of Florida Health Science Center, Jacksonville, FL. Review provided by VeriMed Healthcare Network.
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Page last updated: 29 January 2009 |