Stroke

Katie YurginBIO 105-05

Professor Allen

Types of stroke

• A stroke is a medical emergency. Strokes happen when blood flow to your brain stops. Within minutes, brain cells begin to die.

• Two types of stroke: Ischemic stroke- is caused by a blood clot that blocks

or plugs a blood vessel in the brain. Hemorrhagic stroke- is caused by a blood vessel that breaks and bleeds into the brain. "Mini-strokes" or transient ischemic attacks (TIAs), occur when the blood supply to the brain is briefly interrupted.

Signs and Symptoms

• Sudden numbness or weakness of the face, arm or leg (especially on one side of the body)

• Sudden confusion• Trouble speaking or understanding speech• Sudden trouble seeing in one or both eyes• Sudden trouble walking, dizziness, loss of

balance or coordination• Sudden severe headache

Time is Crucial!• Seek immediate medical attention!!! • Signs and symptoms may fluctuate or disappear. • Call 911 or your local emergency number right away. Every minute

counts. Don't wait to see if symptoms go away. The longer a stroke goes untreated, the greater the potential for brain damage and disability.

• To maximize the effectiveness of evaluation and treatment, you'll need to be treated at a hospital within three hours after your first symptoms appeared.

Risk factors• High blood pressure • Cigarette smoking or exposure to secondhand smoke. • High cholesterol • Being overweight or obese • Physical inactivity. • Obstructive sleep apnea • Cardiovascular disease • Use of some birth control pills or hormone therapies that include estrogen. • Heavy or binge drinking• Drug use• Women with high blood pressure who take oral contraceptives are at

higher risk of stroke. • Personal or family history of stroke • Being age 55 or older.

Complications• A stroke can sometimes cause temporary or permanent

disabilities, depending on how long the brain suffers a lack of blood flow and which part was affected.

• Complications may include: • Paralysis or loss of muscle movement. Lack of blood flow to the brain can

cause you to become paralyzed on one side of your body.• Difficulty talking or swallowing.• Slurred speech• Difficulty with language. (aphasia), including speaking or understanding

speech, reading or writing. • Memory loss or thinking difficulties. • Emotional problems. People who have had strokes may have more difficulty

controlling their emotions, or they may develop depression.• Pain and numbness. Some people who have had strokes may have pain,

numbness or other strange sensations in parts of their bodies.

Emergency treatments for stroke:

• Emergency treatment following a stroke may include the following:

• Medications used to the dissolve blood clot(s) that cause an ischemic stroke:Medications that dissolve clots are called thrombolytic or fibrinolytic and are commonly known as “clot busters.”

- Reduces damage to brain cells caused by the stroke. - Should be given within several hours of a stroke's onset.• Medications and therapy to reduce or control brain swelling:

Corticosteroids and special types of intravenous (IV) fluids - Help reduce or control brain swelling, especially after a hemorrhagic stroke• Life support measures -ventilators (machines to assist with breathing), IV

fluids, adequate nutrition, blood pressure control, and prevention of complications.

Other Treatments:

• Surgery may be needed to remove blood clots.• Physical Therapy• Speech Therapy

Research and Studies

• According to the American Academy of Sleep Medicine, around 30% of the US population has insomnia. Insomniacs are at much higher risk of stroke than those without the sleep disorder.

• Individuals with insomnia had a 54% increased risk of hospitalization for stroke, compared with non-insomniacs. Insomniacs who were diagnosed with the disorder between 18 and 35 years old were eight times more likely to be hospitalized for stroke than those without insomnia.

Additional Research• Long-term brain damage caused by stroke could be reduced by saving cells

called pericytes that control blood flow in capillaries, reports a new study led by scientists from UCL (University College London).

• Until now, many scientists believed that blood flow within the brain was solely controlled by changes in the diameter of arterioles, blood vessels that branch out from arteries into smaller capillaries. The latest research reveals that the brain's blood supply is in fact chiefly controlled by the narrowing or widening of capillaries as pericytes tighten or loosen around them.

• The study, published in Nature, shows not only that pericytes are the main regulator of blood flow to the brain, but also that they tighten and die around capillaries after stroke. This significantly impairs blood flow in the long term, causing lasting damage to brain cells. The team of scientists from UCL, Oxford University and the University of Copenhagen showed that certain chemicals could halve pericyte death from simulated stroke in the lab, and hope to develop these into drugs to treat stroke victims.

Works Cited• "Cell-saving Drugs Could Reduce Brain Damage after Stroke."

ScienceDaily. ScienceDaily, n.d. Web. 05 Apr. 2014. <http://www.sciencedaily.com/releases/2014/03/140326153721.htm>.

• Medical News Today. MediLexicon International, n.d. Web. 05 Apr. 2014. <http://www.medicalnewstoday.com/articles/274985.php>.

• "Stroke: MedlinePlus." U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 04 Apr. 2014. <http://www.nlm.nih.gov/medlineplus/stroke.html>.

• "Stroke." Prevention. N.p., n.d. Web. 03 Apr. 2014. <http://www.mayoclinic.org/diseases-conditions/stroke/basics/prevention/con-20042884>.

• "Treatment for Stroke." - The University of Chicago Medicine. N.p., n.d. Web. 05 Apr. 2014. <http://www.uchospitals.edu/online-library/content%3DP00806>.