Types of tonometers: device and principle of operation, popular brands of tonometers

Blood pressure is one of the most important indicators of human health. If it often rises, then this is a disease, and a large excess of the norm carries a danger to life. Almost half of humanity suffers from hypertension - you need to constantly monitor the pressure. Therefore, it is so important to have a tonometer on hand. We will figure out what types of blood pressure monitors are convenient to use and how to choose the best and inexpensive.

What tonometers are

A blood pressure monitor is a special device for measuring blood pressure. The indicators are displayed immediately and give complete information about the level of blood pressure and heart rate. Any deviations from the norm are manifested by unpleasant symptoms: headache, nausea, dizziness.

The modern market pleases with various instruments for measuring the indicators in question. They differ in the set of functions performed, accuracy of indications, dimensions and cost.

There are two types of devices: mechanical and electronic. The first are divided into semi-automatic and automatic. Fully automated devices are divided into two subspecies: mount on the shoulder and on the wrist. They all differ in type and order of measurement, also have pros and cons. But the most accurate and reliable are considered automatic models. For home use, you can purchase any of them, it is important to consider the functionality of the device, its cost and reliability.

Mechanical tonometer device and principle of operation

Mechanical devices are divided into mercury manometers and membrane.

How does a mercury manometer work?

Mercury pressure gauge

The very first instrument for measuring performance was a mechanical mercury. Currently, it is practically not used. But it is considered the most accurate instrument that measures blood pressure. It differs from modern ones by the presence of a mercury scale. Her column rises to the desired number - this is blood pressure. The rest of the devices do not differ from modern ones: a cuff mounted on the shoulder, a pump for air supply, a phonendoscope for picking up tones. The device is unsafe - in case of careless movement, the scale with mercury can fall out and break, and poisonous liquid will spread on the floor. Therefore, this device is no longer used.

How does a mechanical membrane tonometer work?

His work is due to the presence of a sensitive part - a membrane. This is a flexible plate that bends under pressure and, under the action of additional mechanisms, moves the arrow on the gauge scale. The device quite accurately displays an indicator of the state of health, is safe and has a wide range of applications. He is considered a professional tonometer, all medical institutions are equipped with it. For proper use skills are required, they are trained by medical personnel. At home, it’s difficult to measure pressure on your own, the main difficulty is listening to tones.

Mechanical blood pressure monitor

The measurement order is as follows:

1. Place the cuff on the forearm, slightly above the fold of the elbow.
2. Place the phonendoscope on a vessel in the bend area.
3. Fill the cuff with air using a pear.
4. Gradually releasing air from the cuff with a special valve, listen to the tones and look at the arrow.
5. The first “knocking” is systolic pressure.
6. Final - a diastolic indicator.

Modern manufacturers simplify the device. There are models with a phonendoscope inserted in the cuff. And some have a pear combined with a scale.

Advantages mechanical tonometer are listed by the following factors:

• low cost;
• high accuracy of measurement;
• simple device and durability of use.

The disadvantages of the device include:

• measurement requires special skills, fine hearing and good eyesight;
• it is difficult to measure without outside help, otherwise the indicators will be distorted;
• no additional features.

For home use, it is better to purchase a different type of tonometer.

About electronic devices

Electronic devices are divided into semi-automatic and automatic. A similar principle of operation, but there is a difference in use.

How does a semi-automatic blood pressure monitor work?

Semi-automatic blood pressure monitor

This type of device also has a pear and cuffs, but instead of a scale - an electronic screen and buttons for control. It is quite similar to a mechanical apparatus, but more simple to operate. A pear needs to fill the cuff with air, and then wait until the tonometer itself processes the signals and displays the indicators in large numbers on the scoreboard.

The tonometer works from an electric network or on batteries. The device is compact, fairly accurate in readings and equipped with additional features.

The advantages of the device are in the following features:

• good accuracy, error up to 3 mm RT. Art;
• average cost;
• no need to listen to the “knocking” and follow the gauge needle;
• compact, it is convenient to carry with you;
• there is little electronics and the risk of breakdowns is reduced;
• equipped with functions such as determining the rhythm of the heart, is able to remember the time of the previous measurement.

The device also has negative sides:

• air supply with a pear increases the risk of distortion in measurements, it is especially difficult for elderly people;
• there is a need to replace the batteries, their discharge usually happens at the wrong time;
• breakdowns that require repair in the workshop also occur.

But he is still the most popular tonometer used in everyday life.

Electronic blood pressure monitor: what are its operating principles?

This is the most expensive device of all types of tonometers. The cuff and the electronic device connected to it are included in the package. As soon as the cuff is put on the forearm and the button is pressed, the electric pump built into the device pumps air into it. The entire measurement process takes place automatically, the sensors process the indicators and issue them in digital image on the display screen. Tonometers are quite fragile and require careful handling. Easy to use and small in size. No need to ask for outside help, but just sit comfortably and relax. It can work from a network or batteries.

Automatic blood pressure monitor

Pluses of an electronic tonometer:

• they can measure blood pressure correctly, reducing the risk of incorrect readings;
• measurement error - 3-5 mm RT. Art;
• the procedure is quite simple and accessible to older people;
• small-sized device.

But the latest tonometer model also has disadvantages:

• high price;
• the presence of error;
• short service life.

The new models of blood pressure monitors have many different functions that allow you to track not only pressure. It is necessary to list only the most popular and common:

• the device recalls the time of the previous use;
• the presence of an arrhythmia indicator;
• the presence of an indicator of the correct cuff fixing;
• shows the average result of several measurements;
• automatically shuts off after work.

There are other functions, such as a calendar, a clock, indicators for inflation of the cuff, and many others.

Wrist Mounted Blood Pressure Monitor

Among electronic blood pressure monitors there is a model that measures pressure on the wrist. This device does not have a cuff, but simply is fixed in the wrist area, indicators are displayed on the screen.In order for them to be accurate, fixing the device in place, you need to sit down and relax, keep your hand with the tonometer at chest level.

Wrist device

This model shortens the pressure measurement time and is ideal for athletes, because they can control the performance during training. True, there is a drawback - this is a high error during the exercise. Doctors recommend using this model for people under 40 years old. In the older generation, the vessels wear out, and especially in the area of ​​the wrists, which reduces the reliability of the measurements.

Advantages of the carpal tonometer:

• light weight and dimensions, it can be carried with you everywhere and always;
• simplicity in work, it is not even necessary to undress;
• the ability to take measurements anywhere and even on the run;
• no need to pick up the cuff;
• It has many functions available with a conventional blood pressure monitor.

Cons of the carpal tonometer:

• there are restrictions on the use of age;
• very fragile device, requires careful use;
• when driving shows results with a large error;
• high price.

When buying this type of device, it is necessary to take into account the listed disadvantages and limitations.

How to choose the best

Knowing what tonometers are for measuring blood pressure, all their advantages and disadvantages, you can quite easily pick up a device to use at home. Before making a purchase, you need to know some nuances:

• What diseases does the patient have. The frequency of use of the device and its adaptability to the disease depends on this.
• Can a patient learn to use different types of devices.
• Price policy.

It is important to first decide which device you need: according to the principle of operation or the place of installation. Buy tonometer is better in a pharmacy or a special medical equipment store. First you need to check if there are instructions in the native language, a warranty card, a mark on the verification.

It is also required to inspect the device for build quality, how all the parts are fitted, ease in opening and closing the battery compartment. Check all additional functions, ask the sales assistant to make settings.

A mechanical tonometer guarantees accuracy of pressure measurement and has a low cost, but a person with good hearing and able to learn how to use the device should work with it. Elderly people who themselves monitor their condition, only an automatic blood pressure monitor is suitable. He does everything himself, you don’t even need to spend energy on pumping up the cuff. If the patient had a stroke or heart attack, has arrhythmia, he should have a function of intellectual sensitivity.

The most bought brands

The most sought-after blood pressure monitors are manufactured by Japan's multidisciplinary corporation Omron, AND, and the Japanese high-tech brand Citizen. Also, tonometers of the Swiss corporation Microlife and the American company Meditech are of great demand. Companies are also in demand: Japanese - Nissei and English - B. Well.

List of popular brands

Among the most popular mechanical models are:

• WM-61, B. Well - good accuracy and quality of the pressure gauge. Low price - 780 rubles.

Mechanical tonometer model WM-61, B. Well

• Microlife BP AG 1-40 - large pressure gauge and cuff size. Has a high accuracy of readings. Affordable cost - 1890 rubles.

Tonometer of the Microlife BP AG 1-40 model

• The Ri-Can 141 is an improved model for individual use. Provides maximum accuracy. The price is high - 5950 rubles.

Among the semi-automatic:

• Microlife BP N1Basic - improved quality and accuracy of the test results. Low price - 1450 rubles.
• The Omron S1 is a robust instrument with multiple features. The average price is 1640 rubles.

Semi-automatic model Omron S1

• B. Well WA-22H - excellent accuracy and build quality, improved design, additional design amenities. Low price - 1690 rubles.

Model of a tonometer B. Well WA-22H

The best automatic models:

• Microlife BP A2 Basic is a high-quality universal device for the whole family. The average price is about 3 thousand rubles. It has many features.
• Omron M2 Basic with adapter - reliability of indications and comfort during the work. They can measure indicators once, and this will be the right result. The average cost is 2450 rubles.

Omron M2 Basic with adapter

Cardiologists advise those who are over 40 will be better off purchasing tonometer semiautomatic device or an automatic machine with a cuff on the shoulder. Young people can measure pressure with the wrist.

Acquiring a suitable tonometer for individual use is necessary taking into account all the characteristics of a person, his illnesses, age, and the need for various functions. An instrument is especially required for patients with hypertension and stroke, in order to control pressure and prevent complications.