A device for measuring human pressure. Types of instruments for measuring pressure

A device for measuring pressure is called a tonometer. There are blood pressure monitors to control blood pressure, as well as devices that measure the pressure inside the eye. Quite often they are the very first assistants for a person suffering from blood pressure changes or ophthalmologic problems.

In this article, we will discuss the merits and demerits of different types of such devices and how to use them.

Why do you need to measure blood pressure at home?

If blood circulation is disturbed due to different cardiovascular diseases, the patient needs constant control over arterial pressure.

Measuring blood pressure at home will help both the patient and his attending doctor to follow changes in the indicators throughout the day. A doctor, using a record of measurements, will be able to determine the effectiveness of the drugs used. The very same device for measuring blood pressure will allow taking timely measures to eliminate the hypertensive crisis and, thus, protect yourself from a threatening stroke, while avoiding the "white coat effect", almost inevitable at a doctor's appointment and capable of increasing blood pressure.

What devices are used to measure blood pressure?

In order to be able to control the level of pressure in the blood vessels, mechanical, automatic or semi-automatic tonometers are used. Each of them has its advantages and disadvantages.

The mechanical tonometer has a sensor that can be read by looking at the arrow moving on the dial. The cuff of this device is attached at the top of the hand, closer to the shoulder. It contains an air tank and is pumped by hand, using a rubber pear.

The mechanical device for measuring blood pressure, according to most consumers, demonstrates the most accurate indicators and is at the same time much cheaper than its electronic counterparts.

How to use a mechanical tonometer

But, unfortunately, a mechanical tonometer can be quite difficult to use, because this device for measuring blood pressure requires certain skills and good hearing from the user. For a mechanical tonometer, the use of a phonendoscope is required, with the help of which the cardiac contractions are listened.

Fonendoscope attach to the artery in the arm bend. Vigorously inflate the air in the cuff with a pear, up to about 180 mm Hg. Art. Or 30 points higher than the latest performance of the device. Then, loosening the valve on the pear, slowly release air from the cuff (with a rapid air outlet you will not be able to determine the pressure).

As soon as blood begins to flow into the arteries, there is a pounding sound - at this time, you should notice the first digit on the sensor. It shows the systolic (upper) pressure. At the moment when the sound disappears, notice one more digit - this is the diastolic (lower) pressure.

If you need to repeat the measurement, take a break for 2-3 minutes.

What to do before you start measuring blood pressure

But that your, even the best, device for measuring the pressure showed the correct figures, you should observe several general rules.

1. Before you start the measurement procedure, do not physically strain, do not eat or drink beverages containing caffeine or alcohol, at least half an hour before the procedure. You should not smoke, too, because this process can distort data.
2. Try to empty the bladder.
3. Before the beginning of the procedure, rest about 5 minutes, and if you are nervous or exerted physical effort, rest should last at least 15 minutes.
4. Do not talk during pressure measurement.
5. Take care that the sleeve of clothing does not fall under the cuff.
6. Take a comfortable position. Do not cross your legs, with your back leaning your elbows on the back of a chair.
7. Pressure should be measured on the same hand. Put it on the table or armrest and do not move.
8. When measuring the pressure on the wrist, it is required to lift the arm bent at the elbow to the level of the heart.
9. The cuff around the arm should be wrapped tightly. If it should be located closer to the shoulder, then make sure that there is at least 3 cm of space between the elbow and the cuff.

If the result of pressure measurement frightened you, calm down and measure again after a few minutes. Sometimes it is found that everything is not as scary as it seemed at the first measurement. And be sure to remember that at a pressure exceeding 180/120 mm Hg. Art., You need mandatory medical attention!

Why you need to re-measure pressure several times in a row

Most often, the first result after measuring the pressure is overestimated, because due to the strong contraction of the arm by the cuff, the blood vessels involuntarily increase in tone. Therefore, the device for measuring human pressure is best used 3 times in a row on one hand, with small intervals. If the indicators of the second and third dimensions are as close as possible, then this is the numbers of your pressure. If the repetition of values is not observed, measure it up to 8 times (also with interruptions) until you find a stable repeatability. These figures will be the most accurate.

By the way, immediately after purchase, measure the pressure on both hands. And if on one of them it is higher, then the following measures it on it.

How is an automatic and semi-automatic pressure measuring device used?

Automatic and semi-automatic device for measuring human pressure is much easier to use. To do this, just put the cuff on your arm and press the "Start" button. The cuff will start to inflate on its own. True, on semi-automatic devices it will need to be pumped with a pear. But the use of phonendoscope in both cases is completely unnecessary, since the electronic sensor, built into the cuff, itself detects blood flow and draws conclusions. The results of the pressure measurement are visible on the screen.

There are both automatic devices, the cuff of which is located on the wrist, and those where the cuff is attached above the elbow.

By the way, when choosing a device, you should always pay attention to the size of the cuff. Since in case it turns out to be small-sized, the device can overstate the indicators, and with a wide cuff - understate them.

How to choose a tonometer for home use

Most often, obviously because of ease of use, consumers choose a semi-automatic or automatic pressure measuring device. They can be bought at every pharmacy, but still you should not rush.

First of all, think about which of the two types of devices is more convenient for you. Be sure, as already mentioned, pay attention to the size of the cuff. They come in three sizes:

• S (small, up to 22 cm);
• M (medium, up to 32 cm);
• L (large, up to 45 cm).

Consider the display: the numbers on it should be clear and well-visible. Ask the seller how accurate this model of the tonometer is.

Are there any shortcomings in automatic tonometers?

Of course, automation greatly facilitates the process of measuring pressure, but such devices have their drawbacks. They are not very accurate, they require mandatory calibration of sensors in special service centers, and their price is seriously higher than for mechanical tonometers, in addition, they serve less than the named devices.

The electronic device for measuring pressure is powered by batteries, and their power is not enough to create the necessary pressure in the cuff for a long time. As a rule, this leads not only to the fact that the batteries sit down - the device itself also quickly deteriorates.

Although do not get it literally. Modern automatic and semiautomatic tonometers can last for many years, but their mechanical counterparts will still be on guard for your blood pressure for much longer.

Which pressure measuring devices are better?

In the market of tonometers, the most popular today are the devices of the companies "Omron", "Microlife", and also "AND". These are quite accurate, durable and easy-to-use devices produced in Japan, Switzerland and the USA and for many years holding the palm tree in this field. Which of these tonometers you give preference to, it's up to you, since among the listed, each device for measuring the pressure of the reviews is excellent.

What is the intraocular pressure

Elevated blood pressure can also affect the condition of our eyes. It turns out that with hypertension, blood pressure on small vessels, which, in turn, leads to an increase in the pressure of intraocular contents (permeated with capillaries) on the eye walls. This increases the pressure inside the eye.

Intraocular pressure is a tone created by a constant inflow and outflow of fluid inside the eyeball. Its normal values are from 16 to 24 mm Hg. Art. For human health, both prolonged high blood pressure inside the eye (glaucoma) and low (hypotension) is dangerous.

A modern device for measuring eye pressure allows us to do this without causing inconvenience to the patient, although the practice of Russian healthcare still uses the Maklakov tonometer, which patients dislike.

How is the intraocular pressure measured

In order to measure intraocular pressure with the help of the said tonometer, after the procedure of anesthesia, specially painted weights are placed on the center of the cornea of both eyes of the patient. Their imprint is then measured and decoded.

This device for measuring intraocular pressure requires mandatory disinfection and good knowledge from the specialist who conducts the procedure. By the way, it is mandatory to instill a disinfectant into the eyes and after the measurement.

It should be remembered that in women the intraocular pressure is usually higher than that of the stronger sex. In addition, the indices of pressure increase with age. High intraocular pressure may be a sign of glaucoma or a signal of the possibility of its development.

Non-contact method of measuring intraocular pressure

Unlike the tonometer Maklakov, the contactless tonometer excludes infection, because during the procedure there is no need to touch it with the cornea. In addition, a non-contact device for measuring intraocular pressure is used without anesthesia.

Pressure using this device is measured through the eyelid, with a high speed and no feeling of discomfort. And the procedure can be carried out by the patient himself, if necessary.

True, this device is not suitable for those who have scars on the eyelid, inflammation or any deformity of this part of the eye. Do not use this device and with conjunctivitis or severe pathological condition of the sclera.

International method for measuring intraocular pressure

By the way, different instruments for measuring eye pressure can give and different indicators of the norm. This sometimes leads to arguments between adherents of this or that technique.

So, in international practice, till now, the most accurate tonometry according to Goldman is considered. This measurement method is based on observing exactly what force is required to flatten the eye cornea by a fixed diameter (it is 3.06 mm). The instrument used to measure human pressure is calibrated in such a way that the readings of its force are displayed on a graduated scale.

The doctor directs a bright light into the patient's eyes and sees this organ through that plastic cylinder, which flattens the cornea. Before this, a special dye (fluorescein) is instilled in the conjunctive bag, which, when the cornea touches the sensor, is shifted to the sides. The doctor at the same time sees through the cylinder-microscope the glowing semirings. To him, in order to determine IOP, it is necessary to wait for the connection of the inner surface of the upper and lower half rings, while adjusting the pressure scale. The norm for this measurement ranges from 9 to 21 mm Hg. Art.

What is imprinted tonometry for Stolz

With tonometry according to Stolz, the indications are taken from several points on each eye of the patient. The doctor for this softly touches the cornea, determining the level of IOP by the depth of depression of the rod of constant cross-section. At the same time, a click is heard as soon as the readout begins. And after the sound signal, you can see the average data on intraocular pressure on the display.

There is a device for self-measurement of intraocular pressure

If a patient is diagnosed with glaucoma, he needs to monitor the effect of medications and IOP readings at home. In this, it will be helped by a device based on a ricochet measurement of pressure.

The use of this device does not require drops for anesthesia or special skills, since the sensor only touches the cornea lightly for a moment.

The tonometer has two support elements that can be adjusted, as well as an LED indicator. The described device for measuring human pressure displays 11 pressure zones with a range of 5 to 50 mm Hg. Art. If the pressure inside the eye is high, the device emits warning signals. Another advantage is that the risk of infection is excluded, since the tonometer has disposable sensors.