According to the National Stroke Association, stroke is the No. 3 cause of death in the United States. Still, as many as 80 percent of such deaths are avoidable if people know what signs and symptoms to look for.
Symptoms & Causes
A stroke occurs when the brain does not receive enough oxygen-carrying blood. Within minutes, brain cells may begin to die. There are a couple types of stroke, but the most common is an ischemic stroke.
Ischemic stroke involves the blockage of an artery to the brain. An ischemic stroke may be described as thrombotic (a blood clot created by the buildup of plaques in arteries) or embolic. An embolic stroke is caused when a blood clot, or embolus, forms in the heart or another area far from the brain, and then travels through the bloodstream, and lodges in small brain arteries.
Hemorrhagic stroke happens when a blood vessel in the brain begins to leak blood. This type of stroke is typically caused by high blood pressure, which affects the integrity of blood vessels, or by weak areas of blood vessels. Hemorrhagic stroke can be further divided into two types.
Intracerebral hemorrhagic stroke involves blood leaking from a vessel onto surrounding brain tissues. This damages nearby cells, as well as other parts of the brain.
Subarachnoid hemorrhagic stroke involves blood leaking into what is called the subarachnoid space, the area between the brain and the skull. An intense headache can occur with this type of stroke.
It is also possible that individuals experiencing stroke symptoms are in fact having a ministroke, or transient ischemic attack. The same things cause a ministroke as an ischemic stroke, but the attack is only temporary and the effects are not permanent. Still, a ministroke indicates an individual is at risk of having a stroke. Furthermore, there is no way to tell the difference between a ministroke and a real stroke until an individual undergoes testing at a medical facility.
There are several signs that indicate stroke has occurred. According to the American Stroke Association, they include the sudden onset of:
If any of these symptoms appear, note the time and call 9-1-1. Within 3 hours of symptoms beginning, drugs that can remove blockages in arteries may be administered to prevent permanent disability or death.
Diagnosis & Tests
To diagnose stroke, physicians perform a physical exam and blood tests. Imaging is also sometimes used. Computerized tomography, or CT scan, helps to confirm whether an individual is having a stroke, and what type of stroke is present. A more specialized CT scan uses dye injected in the vein to view the structure of the arteries.
Magnetic resonance imaging, MRI, allows physicians to view any brain tissue damage.
A carotid ultrasound can indicate clotting in the carotid artery, a major artery that runs up the neck into the brain. Another type of ultrasound, called echocardiography, shows images of the heart, allowing physicians to determine whether the stroke has resulted from an embolus.
If parts of the brain are denied oxygen for too long, severe damage can result. Individuals may be paralyzed on one side of the body, or just the face. Stroke can affect the ability to swallow and eat.
Communicating may be difficult if stroke causes aphasia, a condition that results when areas of the brain that control thought processing and language are damaged. Memory and reasoning abilities may be impaired. Moreover, behavior may change. Individuals may become more isolated and some may require daily care.
In some cases, people may experience pain in various areas of the body.
Treatments & Medications
Treatments differ for ischemic and hemorrhagic stroke.
The primary goal in treating ischemic stroke is to restore the brain's blood flow. Medications that destroy clots in blood vessels are ideally given within the first four-and-a-half hours of the stroke. Typically the drug administered is aspirin.
Some individuals may be given an injection of tissue plasminogen activator (TPA) to further improve the likelihood of a full recovery. However, there is a limited window of opportunity for using this method. Or, the TPA may be administered to the area experiencing stroke through a catheter in the groin.
The goal in treating hemorrhagic stroke is to reduce pressure on the brain and stop bleeding. In contrast to blood thinners given for an ischemic stroke, clotting drugs may be given to individuals who regularly take drugs like warfarin.
As soon as bleeding is under control and the area is healed, a surgeon will repair the leaky and damaged blood vessels.
Long-term rehabilitation programs are often able to help improve, or at least manage, stroke complications.