The device for measuring pressure is called a tonometer. There are blood pressure monitors, as well as instruments that measure pressure inside the eye. Quite often they turn out to be the very first helpers for a person suffering from drops in blood pressure or ophthalmic problems.
In our article, we will discuss the advantages and disadvantages of different types of such devices and how to use them.
Why measure blood pressure at home?
In case of circulatory disturbance caused by various diseases of the cardiovascular system, the patient requires constant monitoring of blood pressure.
Measuring blood pressure at home will help both the patient and his treating doctor to monitor changes in indicators throughout the day. And the doctor, using the recording of measurements, will be able to determine the effectiveness of the drugs used. The device for measuring blood pressure will allow the patient to take timely measures to eliminate the hypertensive crisis and, thus, protect himself from an imminent stroke, while avoiding the “white coat effect”, which is almost inevitable at the doctor’s appointment and can increase blood pressure.
What devices are used to measure blood pressure?
In order to be able to control the pressure level in the blood vessels, mechanical, automatic or semi-automatic blood pressure monitors are used. Each of them has its advantages and disadvantages.
The mechanical blood pressure monitor has a sensor that can be read by looking at the arrow moving along the dial. The cuff of this device is attached to the upper arm, closer to the shoulder. It contains an air tank and is manually pumped using a rubber bulb.
A mechanical device for measuring blood pressure, according to most consumers, demonstrates the most accurate indicators and costs much less than its electronic counterparts.
How to use a mechanical tonometer
But, unfortunately, a mechanical tonometer can be quite difficult to use, since this device for measuring blood pressure requires certain skills and good hearing from the user. A mechanical tonometer requires the use of a phonendoscope, with which heartbeats are heard.
Phonendoscope attach to the artery at the bend of the arm. Vigorously pump air into the cuff with a pear, up to about 180 mmHg. Art. or 30 points higher than the last indicators of the device. Then, loosening the valve on the pear, you should slowly let the air out of the cuff (you will not be able to determine the pressure with a quick air outlet).
As soon as the blood begins to flow in the arteries, a knocking sound appears - at this time the first digit on the sensor should be noted. It shows systolic (upper) pressure. At the moment when the sound disappears, one more figure is noticed - this is diastolic (lower) pressure.
If you need to repeat the measurement, take a break for 2-3 minutes.
What to do before starting a blood pressure measurement
But in order for your, even the best, pressure measuring device to show the correct numbers, several general rules should be followed.
- Before you begin the measurement procedure, do not physically strain, eat or drink beverages containing caffeine or alcohol, at least half an hour before the procedure. You should also not smoke, because this process is capable of distorting the data.
- Try to empty your bladder.
- Before starting the procedure, rest for about 5 minutes, and if you are nervous or have made physical efforts, rest should last at least 15 minutes.
- Do not talk while measuring pressure.
- Make sure that the sleeve of the clothes does not fall under the cuff.
- Take a comfortable position. Do not cross your legs; lean your back against the back of a chair.
- Pressure is best measured on the same arm. Lay it on a table or armrest and do not move it.
- When measuring pressure on the wrist, it is necessary to raise the arm bent at the elbow to the level of the heart.
- 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 space between the elbow and the cuff.
If the result of the pressure measurement scared you, calm down and measure again after a few minutes. Sometimes it turns out that everything is not as scary as it seemed in the first measurement. And be sure to remember that at a pressure exceeding 180/120 mm Hg. Art., you require compulsory medical care!
Why you need to measure the pressure several times in a row
Most often, the first result after measuring the pressure is overestimated, because due to the strong compression of the arm, the cuff of the blood vessels involuntarily raises the tone. Therefore, a device for measuring human pressure is best used 3 times in a row on one arm, with small intervals. If the indicators of the second and third dimensions are as close as possible, then these are the numbers of your pressure. If a repeat of the values ​​is not observed, remeasure it up to 8 times (also intermittently) until you find stable repeatability. These numbers will be the most correct.
By the way, immediately after the purchase, measure the pressure on both hands. And if it turns out to be higher on one of them, then measure it the next time on it.
How an automatic and semi-automatic pressure measuring device is used
An automatic and semi-automatic device for measuring human pressure is much easier to use. To do this, just need to put the cuff on your hand and press the button: "Start". The cuff will begin to inflate on its own. True, on semi-automatic devices it will need to be pumped with a pear. But the use of a phonendoscope in both cases is completely unnecessary, since the electronic sensor built into the cuff itself detects blood flow and draws conclusions. The pressure measurement results are visible on the screen.
There are both automatic devices, the cuff of which is placed on the wrist, and those where the cuff is attached above the elbow.
By the way, when choosing a device, you should definitely pay attention to the size of the cuff. Since in case it turns out to be small, the device can overestimate the performance, and with a wide cuff, it can underestimate them.
How to choose a tonometer for home use
More often than not, obviously due to ease of use, consumers opt for a semi-automatic or automatic pressure measuring device. You can buy them at every pharmacy, but still do not rush.
First of all, think which of the two types of devices is more convenient for you. Be sure to, 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 clearly visible. Ask the seller how accurate this tonometer model is.
Are there any disadvantages of automatic blood pressure monitors?
Of course, automation greatly facilitates the process of measuring pressure, but such devices also 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 that of mechanical blood pressure monitors, in addition, they serve less than these devices.
The electronic device for measuring pressure is powered by batteries, and their capacity 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 run out - the device itself also quickly becomes worthless.
Although do not take it literally. Modern automatic and semi-automatic blood pressure monitors can last for many years, but their mechanical counterparts will still be on guard of your pressure much longer.
Which pressure gauges are better?
The most popular devices on the tonometer market today are Omron, Microlife, and AND. These are quite accurate, durable and easy-to-use devices manufactured in Japan, Switzerland and the USA and for many years holding the palm in this field. Which of these tonometers do you prefer, is up to you, since among the listed each pressure measuring device has excellent reviews.
What is intraocular pressure?
High blood pressure can also affect the state of our eyes. It turns out that with arterial hypertension, blood presses on small vessels, which, in turn, leads to an increase in pressure of the intraocular contents (penetrated by capillaries) on the eye walls. Thus, the pressure inside the eye increases.
Intraocular pressure is the tone created by the constant influx and outflow of fluid inside the eyeball. Its normal values ​​range from 16 to 24 mm Hg. Art. For human health, both long-term increased pressure inside the eye (glaucoma) and low (hypotension) are dangerous.
A modern device for measuring eye pressure allows you to do this without causing inconvenience to the patient, although the Maklakov tonometer, which patients do not like, is still used in Russian healthcare practice.
How intraocular pressure is measured
In order to measure intraocular pressure using the said tonometer, specially painted weights are placed on the center of the cornea of ​​both eyes of the patient after the anesthesia procedure. Their imprint is then measured and decoded the result.
This device for measuring intraocular pressure requires mandatory disinfection and good knowledge from the specialist conducting the procedure. By the way, it is mandatory to instill a disinfectant solution into the eyes after the measurement.
It should be remembered that in women, usually intraocular pressure is higher than in the stronger sex. In addition, pressure indicators increase with age. High intraocular pressure may be a sign of glaucoma or a signal of the possibility of its development.
Non-contact method for measuring intraocular pressure
Unlike a Maklakov tonometer, a non-contact tonometer excludes infection, since during the procedure there is no need to contact it with the cornea. In addition, a non-contact device for measuring intraocular pressure is used without anesthesia.
Pressure using the named apparatus is measured through the eyelid, with high speed and lack of discomfort. And the procedure, if necessary, can be performed by the patient himself.
True, this device is not suitable for those who have scars on the eyelids, inflammatory processes or any deformations of this part of the eye. Do not use this device with conjunctivitis or severe pathological condition of sclera.
International method for measuring intraocular pressure
By the way, different devices for measuring eye pressure can give different indicators of the norm. This sometimes leads to disputes between adherents of a particular technique.
So, in international practice, Goldman tonometry is still considered the most accurate. This measurement method is based on observing exactly what force is required to flatten the cornea of ​​the eye to a fixed diameter (it is 3.06 mm). The instrument used to measure human pressure is calibrated so that the readings of its strength are displayed on a graduated scale.
The doctor directs a bright light into the patient’s eyes and sees this organ through the plastic cylinder, which flattenes the cornea. Before this, a special dye (fluorescein) is buried in the conjunctival sac, which, when the cornea contacts the sensor, is shifted to the sides. In this case, the doctor sees luminous half rings through a microscope cylinder. In order to determine the IOP, he needs to wait for the connection of the inner surface of the upper and lower half rings, while adjusting the pressure scale. The norm in this measurement ranges from 9 to 21 mm RT. Art.
What is Stolz impression tonometry?
With Stolz tonometry, readings are taken from several points on each eye of the patient. For this, the doctor gently touches the cornea, determining the level of IOP by the depth of the depression of the rod of constant cross section. A click is heard as soon as the reading begins. And after the sound signal, you can see the average data on the intraocular pressure on the display.
There is a device for self-measurement of intraocular pressure
If the patient is diagnosed with glaucoma, he needs to monitor the effects of the drugs taken and the IOP indications at home. A device based on a ricocheted pressure measurement will help him in this.
The use of this device does not require drops for pain relief or special skills, since the sensor only gently touches the cornea for a moment.
The tonometer has two supporting 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 from 5 to 50 mm RT. Art. If the pressure inside the eye is high, the device gives warning signals. Another advantage is the elimination of the risk of infection, since the tonometer has disposable sensors.