Arterial pressure of the person
Human arterial pressure is the total pressure of all arteries in the body. In different arteries, the pressure is different. It is higher, the wider the diameter and closer to the heart. The highest pressure in the aorta is the main vessel, which extends from the left ventricle.
Human arterial pressure consists of two digits: "upper and lower"."Upper" pressure is, so-called, cardiac pressure. It is caused by the work of the heart, the force with which the heart pushes blood into the aorta."Lower" reflects the tone of the vessels of the body, which affects the kidneys. In the kidney parenchyma is located Yuxtaglomerular apparatus, which, when the pressure is lowered, triggers the operation of the angiotensin-aldosterone system, which leads to an increase in water back-up in the kidneys and, correspondingly, an increase in the volume of circulating blood, and an increase in pressure.
Human blood pressure can fluctuate widely: upper - from 90 to 139, and lower - from 60 to 89. There is the concept of operating pressure. This is usually a pressure that is typical of this particular patient is normal.
The arterial pressure of a person can depend on many factors of the external environment: for example, in hot weather it decreases due to reflex dilatation of the vessels( for heat release) and loss of fluid with sweat. If the heart rate increases, for example, due to increased physical activity or fright, the blood pressure may increase. With a sharp change in the position of the body from the horizontal to the vertical, an orthostatic effect may appear, which is manifested by darkening in the eyes and goosebumps. Its origin is due to the fact that the vessels and heart could not react quickly to a change in the position of the body in space, and the pressure was low.
Adjusts the blood pressure of the human nervous system, as well as hormones. Throughout the day, pressure can significantly change its performance. In a dream, it decreases, during the day( especially under stress) - it rises.
It should be noted that different arms can have different blood pressure. But if the difference is less than 5 mm Hg.it does not have clinical significance. Detecting a difference of 10 or more mm Hg. Art.indicates a narrowing of the artery on the arm with less pressure.
The pressure in different age categories may vary slightly. For example, blood pressure in adolescents may be elevated. If its increase is not due to pathology, then hypertension is transient and mild. This is due to the fact that children are usually hyperactive( i.e., they are characterized by increased activity), as well as neuroendocrine regulation during the transition period.
With different physiological states, changes in pressure are possible. For example, blood pressure during pregnancy can increase, which can be a symptom of severe pathology - pre-eclampsia. Therefore, blood pressure in pregnant women should be constantly monitored. If a blood pressure is found to be above normal two times or more within one week, it is necessary to suspect the development of pre-eclampsia.
The normal pressure changes throughout the pregnancy. The pregnancy hormone, progesterone, causes relaxation of the vessel walls, which leads to a decrease in pressure and an increase in the orthostatic effect. The greatest amount of progesterone is produced in the middle of pregnancy - hypotension is possible at this time. By the sixth month of pregnancy in a woman's body contains more than about 2.5 liters of blood - this is an additional burden on her body. In the last days of pregnancy, blood pressure regains its normal values.