Symptoms
Symptoms depend on which part of the brain was affected, as each area has distinct
functions. The extent of the damage determines the severity of the resulting symptoms.
- Facial droop
- Paralysis of limbs (one side of body)
- Paralysis one limb
- Weakness one side of body
- Weakness one limb
- Reduced consciousness
- Depression
- Unable to control elimination of urine/feces
- Fatigue
- Lack of body movement control
- Slurred speech
- Difficulty swallowing
- Difficulty communicating with speech
- Unable to communicate with speech
- Difficulty in coordinating movements
- Loss of sensation one side of body
- Partial loss of sight
- Severe headache
Description
A stroke occurs when the blood supply to the brain is interrupted. This interruption
of blood supply causes irreversible damage to the brain. There are two types of
stroke: Ischemic and Hemorrhagic. The distinction between the two types is determined
by CT and MRI scans.
Ischemic Stroke
This is most common type of stroke, accounting for 87% of stroke cases. An ischemic
stroke occurs when a blood vessel in the brain becomes blocked and is unable to
carry the vital nutrients and oxygen needed for brain function. The blockage is
created by blood vessel plaque, or more commonly, a blood clot. The blood clot normally
develops in the heart or lungs. When the blood clot migrates to the brain via the
circulatory system, it can lodge itself in the smaller blood vessels of the brain
causing a blockage.
Hemorrhagic Stroke
This stroke occurs when an artery in the brain ruptures and bleeds. A subarachnoid
hemorrhage occurs on the surface of the brain under the tissue that covers it. An
intracerebral hemorrhage occurs inside the brain.
Causes
Anyone, regardless of age, race, or gender, can suffer a stroke. However, chances
of suffering a stroke increase if a person has certain risk factors. The most common
risk factors for stroke are high blood pressure, smoking, high cholesterol, and
drinking excess alcohol. Risk factors can be broken into three groups, and when
controlled, the mortality of stroke is reduced.
Non-Modifiable
These are risk factors that cannot be changed such as age, gender, race, and an incidence
of a previous stroke. Some risk factors, such as sickle cell disease (a disease
that causes plaque buildup in the blood vessels), blood clotting abnormalities,
and congenital heart disease are caused by genetics. Fibromuscular dysplasia (a
disease where the artery walls grow abnormal tissue, causing them to narrow and
become obstructed) is an uncontrollable risk factor common in women.
Medically Treatable
These include medical disorders and diseases such as high blood pressure, irregular
heartbeat, high cholesterol, diabetes, and circulatory problems.
Lifestyle Alterable
Stroke development has been linked to modifiable lifestyle factors such as tobacco
smoking, excess alcohol intake, physical inactivity, and obesity.
Treatment
Treatment of stroke requires immediate intervention to stop the bleeding or blockage
and preventative treatment to lower the risk of a subsequent stroke. CT and MRI
scans of the brain are performed to determine whether it is an ischemic or a hemorrhagic
stroke.
Hemorrhagic Stroke
Surgical procedures, such as clipping or coiling of the ruptured blood vessel, are
performed to prevent further bleeding. This takes place as soon as possible after
hospital admission to reduce the rate of bleeding.
Ischemic Stroke
Thrombolytic therapy aims to restore blood flow by clearing the blocked blood vessel.
This is carried out using an intravenous drug, such as alteplase (Activase*), that
helps dissolve blood clots. While in the hospital, a patient is closely monitored
for brain hemorrhage when receiving this type of treatment.
Risk Factors
These are usually managed by drugs. High blood pressure is controlled by blood pressure
lowering agents. For atrial fibrillation, warfarin is often used to reduce the risk
of blood clots forming in the heart. Lipids (fatty acids) that can cause high cholesterol
are reduced by the use of a class of drugs known as statins.
Lifestyle
Smokers are encouraged to stop smoking completely. Any alcohol consumption is advised
to be in moderation and avoid drinking binges. Eating a well-balanced diet is recommended
to control weight and high cholesterol levels. Regular exercise is encouraged to
maintain a healthy body mass index (BMI).