Blood pressure is the pressure of blood within the arteries of the body. Blood pressure is the driving force that causes blood to flow through the body from the arteries (where the pressure is high), through organs, and into the veins (where the pressure is low). Blood pressure is generated by the pumping of blood by the heart into the arteries as well as by the resistance to the flow of blood by the arteries.
Low blood pressure is blood pressure that is so low that it is causing symptoms or signs due to the low flow of blood through the arteries and veins. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidney; the organs do not function normally and may be permanently damaged. It should be noted that unlike high blood pressure, which is defined on the basis of blood pressure alone, low blood pressure is defined primarily by signs and symptoms of low blood flow.
People who have lower blood pressures have a lower risk of strokes, kidney disease, and heart diseases. Athletes, people who exercise regularly, people who maintain ideal body weights, and non-smokers, tend to have lower blood pressures. Therefore, low blood pressure is desirable as long as it is not low enough to cause symptoms and damage to organs in the body.
When the blood pressure is not sufficient to deliver enough blood to the organs of the body, the organs do not work properly and may be permanently damaged. For example, if insufficient blood flows to the brain, brain cells do not receive enough oxygen and nutrients, and a person can feel light-headed, dizzy, or even faint. Going from a sitting or lying position to a standing position often brings out the symptoms of low blood pressure. This occurs because standing causes blood to “settle” in the veins of the lower body, and this can lower the blood pressure. If the blood pressure is already low, standing can make the low pressure worse to the point of causing symptoms.
When there is insufficient blood pressure to deliver blood to the coronary arteries (the arteries that supply blood to the heart’s muscle), a person can develop chest pain (angina) or even a heart attack. When insufficient blood is delivered to the kidneys, the kidneys fail to eliminate wastes from the body, and an increase in their levels in the blood occur.
[Reference from MedicineNet, Inc.]
No comments:
Post a Comment