Why is it important to control any blood pressure changes?
This indicator serves as a sign indicating the state of the organism, and changes in pressure parameters give information about possible diseases. Therefore, it is necessary for a person to be able to determine his own pressure and know what his or her blood pressure should be. So, what is blood pressure? Blood pressure is the pressure of blood on the walls of blood vessels – veins, arteries and capillaries. Blood pressure is necessary in order to ensure that blood can move through the blood vessels.
The amount of blood pressure (sometimes abbreviated as AD) is determined by the strength of the heartbeats, the amount of blood that is thrown into the vessels at each contraction of the heart, the resistance that the walls of the blood vessels exert to the blood flow and, to a lesser extent, the number of heartbeats per unit of time. In addition, the value of blood pressure depends on the amount of blood circulating in the circulatory system, its viscosity. Influence on the value of blood pressure also fluctuations in pressure in the abdominal and thoracic cavities associated with respiratory movements, and other factors.
When blood is injected into the heart, the pressure in it rises until the moment when the blood is expelled from the heart into the vessels. These two phases – the injection of blood into the heart and pushing it into the blood vessels – constitute, in medical terms, the systole of the heart. Then the heart relaxes, and after a kind of “rest” again begins to fill with blood. This stage is called the diastole of the heart. Accordingly, the pressure in the vessels has two extreme values: maximum – systolic, and minimal – diastolic. And the difference in the magnitude of systolic and diastolic pressure, more precisely, fluctuations in their magnitudes, is called pulse pressure. The norm of systolic pressure in large arteries is 110-130 mm Hg, and the diastolic pressure is about 90 mm Hg. in the aorta and about 70 mm Hg. in large arteries. These are the same indicators that are known to us under the name of upper and lower pressure.
How blood pressure is measured?
In medical practice, the blood pressure in the arteries of the hand is most often used. To date, to determine blood pressure, special devices are used – tonometers. As a rule, they are inexpensive and affordable for everyone.
There are three main types of tonometers:
Tonometers can also be digital. Most modern semi-automatic and automatic pressure gauges are digital. Manual tonometers are somewhat cheaper, but require certain skills to work with them, so they are not suitable for the average person.
What is the principle of the tonometer?
The procedure for measuring the pressure is as follows. Around the shoulder, the cuff is wrapped, into which air is pumped. Then it is gradually released. The pressure in the cuff, which coincides with the onset of noise, corresponds to arterial systolic pressure, and the pressure coinciding with the end of the noise is diastolic.
In manual pressure gauges, a stethoscope is used to determine the beginning and end of the noise, the headphones of which are inserted into the ears of the measuring instrument. The air in the cuff is pumped manually with a pear. In automatic and semi-automatic pressure gauges, the pulse and pressure are automatically fixed. The difference between semi-automatic and automatic devices, however, is that in the automatic air in the cuff is pumped by the motor. There are also tonometers that measure pressure on the wrist. They are smaller and more convenient, but less accurate and not suitable for all patients (for example, the elderly). The results of pressure measurements on digital tonometers are usually displayed in three digits, for example, 120 – 70 – 58. This means that the systolic pressure is 120 mm, the diastolic pressure is 70, and the pulse is 58 beats per minute.
Why is it dangerous to have either high or low blood pressure?
During physical exertion and stress, the pressure may increase for some time. This phenomenon is considered normal and is caused by the release into the blood of the vasoconstrictor hormone – adrenaline. However, at rest, the pressure should return to normal. If this does not happen, then this is a cause to start worrying.
- Constantly high blood pressure: the main symptom of hypertension. High pressure leads to a decrease in working capacity, rapid fatigue, dyspnea, pain in the heart, worsening of sleep, increased probability of bleeding. But the most terrible thing is that it significantly increases the risk of such serious illnesses as heart attack and stroke.
- Constantly low blood pressure (hypotension): this condition is not as dangerous as hypertension, but it also does not bode well. With hypotension, the blood supply to tissues worsens, which can lead to a weakening of immunity and other diseases, and the risk of fainting and CNS disorders increases.