From this article you will learn: what are the types of blood pressure, which of its varieties is more important - systolic or diastolic pressure. Why they are singled out separately, what is their norm, and what are the deviations.
The general data on systolic and diastolic pressure
Arterial pressure is an index of the voltage in the lumen of the arterial vascular bed, reflecting the force, withwhich presses blood on the walls of the arteries. The common unit of measurement is millimeters of mercury( mm Hg).This indicator consists of two digits written through an oblique dash( /): the first( upper) displays the systolic and the second( lower) diastolic( eg 130/80 mm Hg)
The systolic pressure shows the tension between the heart and blood vessels at thatthe moment when its reduction takes place - in systole. Therefore it is also called heart.
Diastolic pressure - reflects this tension at the time of its relaxation - in the diastole. Therefore, it is also called vascular.
General data on systolic and diastolic pressure
Blood circulation in the body is due to the well-coordinated work of the cardiovascular system. One of the most important indicators of the normal interaction between the heart and blood vessels is arterial pressure. The heart carries out the function of the pump, which constantly pumps up tension to move the blood through the vessels:
- When the ventricles contract( to the systole), it rises, causing blood to be pushed into the aortic lumen and all other arteries down to the smallest capillaries.
- With the relaxation of the myocardium, the heart cavities expand, the tension in them falls, due to which the blood is filled.
Arterial pressure - this is the blood pressure, which is noted in the arterial vessels as a result of cardiac activity. It can be described as an indicator that reflects how much blood pressure on the walls of the arteries. Regardless of which phase of the cardiac cycle is the contraction or relaxation of the myocardium, the BP remains constant( does not go beyond the norm).This is possible due to the presence of the aortic valve, which opens when the next portion of blood flows into the aorta and closes, preventing its return to the heart when it relaxes.
The system of arterial vessels is necessary in order to transport blood to all organs and tissues. The pressure in it is the main driving force, which consistently pushes blood from the arteries of large diameter to their terminal microscopic branches( capillaries).
Allocate diastolic and systolic pressure. Systolic shows how strongly strained and filled with blood arteries at the time of maximum contractile activity of the heart. Diastolic reflects the minimum value of stress, when the myocardium relaxes, and also how quickly the blood leaves the vessels, passing through the capillaries and microcirculatory bed.
Systolic and diastolic pressure are interrelated, therefore in 90% change of one of them( increase or decrease) is accompanied by a similar change in the second.
On what pressure indicators depend, their norms
The value of blood pressure is affected by the factors that are described in the table.
List of factors | Effect on pressure |
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Cardiac output - the volume of blood that emits the heart at a single reduction | The higher it is, the higher the numbers |
The condition of the walls of the aorta, its valve and large arteries, to which the blood enters immediately after exiting the heart( elasticity, density, ability to stretch( rigidity), surface smoothness) | If they are dense and rigid, the indicator rises( more diastolic pressure) |
Total resistance of small arterial vessels( compressed, spasmodicor are dilated, relaxed) | The more they narrow, the higher the numbers |
The amount of blood that circulates in the vascular space | The less it is, the lower the |
index The ability of the heart to fully reduce, relax, fill and pump | If they are violated, the figures decrease |
The factors listed in the table are considered mechanisms through which diastolic and systolic pressure is maintained:
- by the central nervous system - external influences that are perceivedI'm the brain;
- autonomic nervous system - unconscious reflexes responsible for automatic self-regulation of the body;
- hormonal systems - thyroid gland, adrenal glands, renin-angiotensin system and other biologically active substances;
- individual features of the anatomy and structure of the body, lifestyle features.
To date, the generally accepted norm of blood pressure for adults of all age groups( from young to elderly) is in the range of 100/60 mm Hg. Art.up to 140/90 mm Hg. Art. The figures below and above these indicators are considered pathologies and are called hypotension or hypertension, respectively.
Pressure standards
The standards for children depend on age. They are listed in the table.
Age
Main features of blood pressure for different categories of peoplesuch:
Threatens pressure deviation from the normIn the process of vital activity, diastolic and systolic pressure can briefly( for several minutes) exceed the norm with physical or mental stress or decrease at rest and in sleep. This is considered a valid phenomenon. If the mechanisms of regulation are violated - there is either a steady increase, or a decrease, or a difference. The main causes and consequences, why this occurs, are described in the table:
How to maintain normal pressureThe expressed isolated change in one of the indices - only diastolic or systolic pressure - happens infrequently( about 10%).Usually they deviate synchronously, and the systolic always more than the diastolic pressure. To prevent this, in addition to constant monitoring of tonometry, one should adhere to the general recommendations described in the table.
It is impossible to cope independently with the disturbed blood pressure. Be sure to contact a specialist - cardiologist or therapist to find out the true cause of the abnormalities and eliminate it. |
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