Blood Clots

Blood Clots



hat are blood clots?

Blood is a liquid that flows within blood vessels. It is constantly in motion as the heart pumps blood through arteries to the different organs and cells of the body. The blood is propelled back to the heart in the veins. When muscles contract, they squeeze the veins and allow the blood to be pushed back to the heart.

Blood clotting is an important mechanism to help the body repair injured blood vessels. Blood consists of:

* red blood cells containing hemoglobin that carry oxygen to cells and remove carbon dioxide,

* white blood cells that fight infection, and

* platelets that are part of the clotting process of the body, and

* blood plasma, which contains fluid, chemicals and proteins that are key to bodily functions.

Complex mechanisms exist in the bloodstream to form clots where they are needed. If the lining of the blood vessels becomes damaged, platelets are recruited to the injured area to form an initial plug. These activated platelets release chemicals that start the clotting cascade, activating a series of clotting factors. Ultimately, fibrin is formed, the protein that crosslinks with itself to form a mesh that makes up the final blood clot.

The medical term for a blood clot is a thrombus (plural= thrombi). When a thrombus is formed as part of a normal repair process of the body, there is little consequence. Unfortunately, there are times when a thrombus (blood clot) will form when it is not needed, and this can have potentially significant consequences.

Picture of a blood clot is formed
Picture of how red blood cells and platelets form a blood clot

What causes blood clots?

Blood clots form when there is damage to the lining of a blood vessel, either an artery or a vein. The damage may be obvious, such as a laceration, or may occur on the microscopic level. As well, blood will begin to clot if it stops moving and becomes stagnant.

Venous thrombosis or blood clots in a vein occur when a person becomes immobilized and muscles are not contracting to push blood back to the heart. This stagnant blood begins to form small clots along the lining walls of the vein that gradually grow to partially or completely occlude the vein. An analogy to this process is a slow moving river. Over time, weeds and algae start to accumulate along the banks of the river where the water flows more slowly. Gradually, as the weeds start to grow, they begin to invade the center of the river because they can withstand the pressure of the water.

Arterial thrombi (blood clots in an artery) occur by a different mechanism. For those with atherosclerotic disease, plaque deposits form along the lining of the artery and grow to cause narrowing of the vessel. This is the disease process that may cause heart attack, stroke, and peripheral artery disease. If a plaque ruptures, a blood clot can form at the site of the ruptured plaque that can completely or partially occlude the blood flow at that point.

Blood clots can also form in the heart. In atrial fibrillation, the atrium or upper chamber of the heart does not beat in an organized manner. Instead, it jiggles, and blood tends to become stagnant along the walls of the atrium. Over time, this may cause small blood clots to form. Clots can also form in the ventricle after a heart attack when part of the heart muscle is injured and unable to contract normally. Since the damaged area doesn't contract with the rest of the heart, blood can start to pool or stagnate, leading to clot formation

Allergy/Allergies

Allergy/Allergies


An allergy refers to an exaggerated reaction by our immune system in response to bodily contact with certain foreign substances. It is exaggerated because these foreign substances are usually seen by the body as harmless and no response occurs in non- allergic people. Allergic people's bodies recognize the foreign substance and one part of the immune system is turned on. Allergy-producing substances are called "allergens." Examples of allergens include pollens, dust mite, molds, danders, and foods. To understand the language of allergy it is important to remember that allergens are substances that are foreign to the body and can cause an allergic reaction in certain people.

When an allergen comes in contact with the body, it causes the immune system to develop an allergic reaction in persons who are allergic to it. When you inappropriately react to allergens that are normally harmless to other people, you are having an allergic reaction and can be referred to as allergic or atopic. Therefore, people who are prone to allergies are said to be allergic or "atopic."

Austrian pediatrician Clemens Pirquet (1874-1929) first used the term allergy. He referred to both immunity that was beneficial and to the harmful hypersensitivity as "allergy." The word allergy is derived from the Greek words "allos," meaning different or changed and "ergos," meaning work or action. Allergy roughly refers to an "altered reaction." The word allergy was first used in 1905 to describe the adverse reactions of children who were given repeated shots of horse serum to fight infection. The following year, the term allergy was proposed to explain this unexpected "changed reactivity."

Allergy Fact

* It is estimated that 50 million North Americans are affected by allergic conditions.
* The cost of allergies in the United States is more than $10 billion dollars yearly.
* Allergic rhinitis (nasal allergies) affects about 35 million Americans, 6 million of whom are children.
* Asthma affects 15 million Americans, 5 million of whom are children.
* The number of cases of asthma has doubled over the last 20 years

Earthquake Kit Supplies and Emergency Preparedness

Earthquake Kit Supplies and Emergency Preparedness


While California has been the state most prone to serious earthquakes in recent years, there are many other fault zones in other areas of the United States. For example, geologists and seismologists have predicted a 97 percent chance of a major earthquake in the New Madrid seismic zone of the central United States (including Arkansas, Missouri, Tennessee, and Kentucky) between now and the year 2035. While earthquakes with the power of the one that hit the greater Los Angeles area in January 1994 are fairly rare, less severe earthquakes can interrupt your normal living patterns and cause substantial injury.

During a major earthquake, you may hear a roaring or rumbling sound that gradually grows louder. You may feel a rolling sensation that starts out gently and, within a second or two, grows violent.

Or, you may first be jarred by a violent jolt. A second or two later, you may feel shaking and find it difficult to stand up or move from one room to another.

The real key to surviving an earthquake and reducing your risk of injury lies in planning, preparing, and practicing what you and your family will do if it happens.

Earthquake practice drills

By planning and practicing what to do if an earthquake strikes, you and your family can learn to react correctly and automatically when the shaking begins. During an earthquake, most deaths and injuries are caused by collapsing building materials and heavy falling objects, such as bookcases, cabinets, and heating units. Learn the safe spots in each room of your home. If you have children, get the entire family to practice going to these locations. Participating in an earthquake drill will help children understand what to do in case you are not with them during an earthquake.

Make sure you and your child also understand the school's emergency procedures for disasters. This will help you coordinate where, when, and how to reunite with your child after an earthquake.

During your earthquake drill:

* Get under a sturdy table or desk and hold on to it.

* If you're not near a table or desk, cover your face and head with your arms; and

o stand or crouch in a strongly supported doorway, or

o brace yourself in an inside corner of the house or building.

* Stay clear of windows or glass that could shatter or objects that could fall on you.

* Remember: If inside, stay inside. Many people are injured at entrances of buildings by falling debris.

Earthquake evacuation plans

If an earthquake occurs, you may need to evacuate a damaged area afterward. By planning and practicing for evacuation, you will be better prepared to respond appropriately and efficiently to signs of danger or to directions by civil authorities.

* Take a few minutes with your family to discuss a home evacuation plan. Sketch a floor plan of your home; walk through each room and discuss evacuation details.

* Plan a second way to exit from each room or area, if possible. If you need special equipment, such as a rope ladder, mark where it is located.

* Mark where your emergency food, water, first aid kits, and fire extinguishers are located.

* Mark where the utility switches or valves are located so that they can be turned off, if possible.

* Indicate the location of your family's emergency outdoor meeting place

Smokeless Tobacco

Smokeless Tobacco



Smokeless tobacco is sometimes known as chewing tobacco or spitting tobacco. It is available in two forms, snuff and chewing tobacco. Both types of smokeless tobacco are held in the mouth inside the cheek or between the cheek and gum.

Smokeless tobacco is known to contain at least 28 cancer-causing chemicals, medically known as carcinogens. The main carcinogens in smokeless tobacco are the tobacco-specific nitrosamines (TSNAs). Some of the other cancer-causing agents found in smokeless tobacco are formaldehyde, acetaldehyde, arsenic, benzopyrene, nickel, and cadmium.

Nicotine is also found in smokeless tobacco, like all tobacco products. Although nicotine is absorbed more slowly from smokeless tobacco than from cigarettes, 3 to 4 times more nicotine is absorbed from smokeless tobacco than from a cigarette, and the nicotine from smokeless tobacco remains longer in the bloodstream. Nicotine is the substance responsible for tobacco addiction.

* In 2007, about 3% of U.S. adults aged 26 and older were users of smokeless tobacco, while around 5% of people aged 18 to 25 reported using smokeless tobacco. Rates of use among young people (under the age of 18) are higher than those of adults.

* In 2007, more than 13% of male high school students and more than 2% of female high school students reported using smokeless tobacco.

Smokeless tobacco is not the same thing as smokeless cigarettes. Smokeless cigarettes (also termed e-cigarettes) are designed to provide nicotine in vapor to the user without burning tobacco. However, the smokeless cigarettes still provide addictive nicotine to the user and secondhand nicotine to others.

What are the health risks of smokeless tobacco?

A number of significant health risks are associated with the use of smokeless tobacco.

Cancer risk

Users of smokeless tobacco are at an increased risk (up to 50% according to the American Cancer Society) for certain types of cancer, most notably cancer of the oral cavity (including cancers of the cheek, gums, lips, tongue, and floor and roof of the mouth. Some studies have suggested a link between the use of smokeless tobacco and the development of pancreatic cancer, esophageal cancer, and stomach cancer.

Other health risks
Those who use smokeless tobacco have an increased risk of:

* developing gum diseases and gum recession (pulling away of the gum tissue from the teeth);

* leukoplakia (whitish patches inside the mouth that can become cancerous);

* abrasion (wearing down) of teeth,;

* staining of teeth;

* tooth decay; and

* tooth loss.

All of the above have been linked to smokeless tobacco use.

Some studies have shown a link between an increased risk of cardiovascular disease (including heart attacks and stroke) in users of smokeless tobacco, although these risks are not as great as those observed in smokers. Further research is needed to determine whether or not smokeless tobacco use presents a significant risk of heart disease and stroke

Secondhand Smoke

Secondhand Smoke



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Secondhand Smoke
View Quit-Smoking Tips Slideshow
Quit-Smoking Tips Slideshow Quit-Smoking Tips Slideshow

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: Charles C. P. Davis, MD, PhD

* What is secondhand smoke?
* What causes secondhand smoke?
* What are the health risks of secondhand smoke?
* Lung cancer
* Cardiovascular disease
* Other lung diseases
* Other effects on children
* Effects on pregnant women
* Possible link to breast cancer
* Is there a safe level of secondhand smoke?
* What is thirdhand smoke?
* What can be done about secondhand smoke exposure?
* Secondhand Smoke At A Glance

What is secondhand smoke?

Secondhand smoke refers to tobacco smoke that is passively breathed in by people in the vicinity of a person who is smoking. Terms that have been used to refer to secondhand smoke are passive smoking, involuntary smoking, or environmental tobacco smoke (ETS). Secondhand smoke is a mixture of the smoke from the tobacco product itself (termed sidestream smoke) and exhaled smoke from the smoker (known as mainstream smoke).

When a nonsmoker inhales secondhand smoke, he or she is exposed to the same toxins and chemicals, including nicotine, as the smoker.

Exposure of children to secondhand smoke also increases their health risks; and children are especially vulnerable to the effects of environmental tobacco smoke. About 35% of U.S. children live in homes where smoking occurs regularly. Research has shown that 50% to 75% of children in the U.S. have detectable levels of cotinine (the breakdown product of nicotine) in their blood, so even children who do not live with smokers may be at risk for adverse effects of secondhand smoke. Chemicals from tobacco smoke inhaled by a nursing mother are also known to reach breast milk.

What causes secondhand smoke?

Cigarettes are the most common sources of secondhand smoke, followed by cigars and pipe smokers. People can be exposed to environmental tobacco smoke anywhere - in their homes, in the workplace, and in recreational settings.

What are the health risks of secondhand smoke?

Secondhand smoke carries many health risks. At least 250 harmful chemicals have been identified in secondhand smoke, including at least 50 carcinogens (chemicals that are known to cause cancer). Just some of the dangerous chemicals present in secondhand smoke include vinyl chloride, cadmium, benzene, arsenic, and ethylene oxide.

Secondhand smoke is known to cause cancer. It has been classified as a "known human carcinogen" by the U.S. Environmental Protection Agency (EPA). It is also associated with cardiovascular and respiratory diseases as well as other serious health conditions; several are listed below

Menstrual Cramps (cont.)

Menstrual Cramps (cont.)



Each month, the inner lining of the uterus (the endometrium) builds up in preparation for a possible pregnancy. After ovulation, if the egg is not fertilized by a sperm, no pregnancy will result and the current lining of the uterus is no longer needed. The woman's estrogen and progesterone hormone levels decline, and the lining of the uterus becomes swollen and is eventually shed as the menstrual flow and is replaced by a new lining in the next monthly cycle.

When the old uterine lining begins to break down, molecular compounds called prostaglandins are released. These compounds cause the muscles of the uterus to contract. When the uterine muscles contract, they constrict the blood supply (vasoconstriction) to the endometrium. This contraction blocks the delivery of oxygen to the tissue of the endometrium which, in turn, breaks down and dies. After the death of this tissue, the uterine contractions literally squeeze the old endometrial tissue through the cervix and out of the body by way of the vagina. Other substances known as leukotrienes, which are chemicals that play a role in the inflammatory response, are also elevated at this time and may be related to the development of menstrual cramps.

Why are some cramps so painful?

Menstrual cramps are caused by the uterine contractions that occur in response to prostaglandins and other chemicals. The cramping sensation is intensified when clots or pieces of bloody tissue from the lining of the uterus pass through the cervix, especially if a woman's cervical canal is narrow.

The difference between menstrual cramps that are more painful and those that are less painful may be related to a woman's prostaglandin levels. Women with menstrual cramps have elevated levels of prostaglandins in the endometrium (uterine lining) when compared with women who do not experience cramps. Menstrual cramps are very similar to those a pregnant woman experiences when she is given prostaglandin as a medication to induce labor.

Menstrual Cramps (Dysmenorrhea)

Menstrual Cramps
(Dysmenorrhea)




Menstrual cramps are pains in the abdominal (belly) and pelvic areas that are experienced by a woman as a result of her menstrual period. Menstrual cramps are not the same as the discomfort felt during premenstrual syndrome (PMS), although the symptoms of both disorders can sometimes be experienced as a continual process. Many women suffer from both PMS and menstrual cramps.

Menstrual cramps can range from mild to quite severe. Mild menstrual cramps may be barely noticeable and of short duration - sometimes felt just as a sense of light heaviness in the belly. Severe menstrual cramps can be so painful that they interfere with a woman's regular activities for several days.

How common are menstrual cramps?

Menstrual cramps of some degree affect more than an estimated 50% of women, and among these, up to 15% would describe their menstrual cramps as severe. Surveys of adolescent girls show that over 90% of girls report having menstrual cramps.

What is dysmenorrhea?

The medical term for menstrual cramps is dysmenorrhea. There are two types of dysmenorrhea, primary and secondary.

In primary dysmenorrhea, there is no underlying gynecologic problem causing the pain. This type of cramping may begin within six months to a year following menarche (the beginning of menstruation), the time when a girl starts having menstrual periods. Menstrual cramps typically do not begin until ovulatory menstrual cycles (when an egg is released from the ovaries) occur, and actual menstrual bleeding usually begins before the onset of ovulation. Therefore, an adolescent girl may not experience dysmenorrhea until months to years following the onset of menstruation.

In secondary dysmenorrhea, some underlying abnormal condition (usually involving a woman's reproductive system) contributes to the menstrual pain. Secondary dysmenorrhea may be evident at menarche but, more often, the condition develops later