How to measure blood pressure correctly. Is it possible to measure pressure through clothes Is it possible to measure pressure through a sweater

Jumps in blood pressure levels occur even in people who do not suffer from vascular diseases. You can measure the pressure yourself with a special device - a tonometer.

Measurement results may show a different value even if measurements are taken in a very short period. Therefore, in order to obtain reliable data, you need to follow some rules, they will help to minimize the error in the results.

General measurement rules

These rules apply regardless of what type of tonometer is used. When measuring pressure with an electronic device, you need to be more careful, as it is more sensitive than a mechanical one.

The position of the person to whom pressure is measured should be comfortable: sitting or lying down. In the sitting position, the hand is placed on the table in a relaxed state.

• The temperature in the room should be comfortable.
• The cuff of the blood pressure monitor should be fixed on the shoulder in line with the heart.
• During the procedure, you should not talk, clench your palm into a fist or put the palm of your other hand under your arm.
• If blood pressure monitoring occurs systematically (for example, in case of illness), it should be carried out at the same time. It is best to do this before meals.
• The cuff must cover at least 80% of the circumference of the upper arm. When measuring in an obese person, be sure to use a cuff with an extended air chamber. In addition, it should be applied to bare skin, and not to the sleeve of clothing.
• Inflate the cuff quickly and deflate slowly.
• Half an hour to an hour before the procedure, you should refrain from smoking, eating products containing caffeine, as well as from physical activity.

The main errors in the measurement

• The hand is at the wrong level. The device may show an overestimated value if the hand is below the level of the heart. Accordingly, if the hand is above the level of the heart, the results will be underestimated.
• The man has nothing to lean on. The device will show pressure higher than the real one.
• A tightly tightened cuff will also affect the measurement result in a big way. It should be worn tightly, but not tight.
• A cuff worn over clothing can also give a large error in measurements. Sleeves should be turned up but not rolled up.
• At rest, the pressure gauge pointer is not set to 0. Before measuring, the device must be calibrated.
• Insufficient inflation of the cuff. In this case, the device will show an underestimated systolic pressure.
• Inflate the cuff evenly. If the inflation is too slow, the diastolic pressure reading will be too high. And when too fast, the systolic is underestimated and the diastolic is overestimated.
• Errors in the results always give a conversation or movement during the procedure.
• Measurements taken immediately after sports or physical activity will show rather high values.
• Distorted results can be obtained if the pressure is measured several times at short intervals. During measurements, the blood stagnates, it is necessary to withstand a period of time of at least a minute for re-measurement. Then the results will be correct.

Difference in readings in AT measurements on different hands

The results of measurements on the right and left hands may differ. This is due to the anatomical feature of the heart: in the vessels that go to the right and left hands, the blood pressure is different. This difference can reach up to 30 mm Hg. Art.

Thus, by obtaining normal readings on the left arm, one can miss the hypertension that would be visible when measuring the pressure on the right arm.

Despite this, almost all doctors take measurements on the left hand. They attribute this to the comfortable position of the patient.

In the instructions for devices for measuring blood pressure, the left hand is also often indicated as recommended for taking measurements.

To obtain a real level of pressure, it is correct to take measurements on both hands. The highest figure will be reliable. From now on, it is necessary to measure the pressure on the arm where the pressure level was higher.

In some cases, the difference in pressure in the arteries in different hands may be insignificant or even absent. In this case, in order to determine on which hand the pressure should be measured, it is recommended to adhere to the following rule: for right-handers, pressure is measured on the left hand, for left-handers - on the right.

Factors affecting measurement results

• Caffeine and nicotine. Products that contain caffeine (coffee, tea, chocolate and some carbonated drinks) can raise blood pressure levels by 5-15 mm Hg. Art. In a person who is not used to caffeinated products, they can cause a sharp jump in blood pressure.

The same short-term effect of increasing pressure causes smoking. Immediately after smoking a cigarette, systolic and diastolic pressures increase by 10-30 mm Hg. Art. They return to normal after about half an hour.

• Medicines. 2 hours before measuring pressure, you should exclude the use of drugs that affect the functioning of the cardiovascular system. Unwanted drugs also include eye and nasal drops and sprays. They temporarily increase the level of pressure.
• Arrhythmia. With this pathology, the principle of determining pressure depends on what form of arrhythmia a person suffers from. Electronic blood pressure monitors can give an accurate result if the pulse signal is of sufficient quality. But in some forms of arrhythmia, it is erratic and the results may be incorrect. In any case, it will be correct to take measurements several times and calculate the arithmetic mean.
• Position. Uncomfortable or incorrect body position during the measurement procedure can give a large error in the results. It is necessary to lean back in a chair, hands are in a relaxed state, not leaning on anything. The hand on which the measurement is carried out should lie, but not hang.

Also, you can not cross your legs and sit cross-legged. This can occlude large arteries, resulting in incorrect measurement results.

• Cold room. It is necessary to measure the pressure at an air temperature of about 20 degrees. At lower temperatures, the measurement results will be higher.
• Crowded bowels and bladder, bowel spasm. All of these factors contribute to high blood pressure. It is better to measure the pressure a few minutes after emptying the bladder.

So, it is correct to measure blood pressure on both hands (and not on the left, as everyone usually does), given the highest value.

The different value of its level on the right and left hands is not a pathology, it is a physiological norm. If the readings taken from both hands are the same, in the future it is enough to take measurements from one hand.

Before the procedure, it is always worth considering all the factors that greatly distort the measurement results. For example, using a cold spray right before starting the procedure will increase the readings in the results. And during the measurement itself, follow the rules that will reduce the measurement error.

Cardiologist of the Cardiology Department Bukina G.V.

Many of us know that we should measure our own pressure regularly. After all, not always its increase or decrease is felt physically.

Everyone needs it

Headache, weakness, dizziness, and tinnitus may or may not accompany these changes. Often, even with critical figures of pressure, people feel pretty well. Therefore, the purchase of a tonometer is a necessary thing for every family. This thing is especially needed for elderly and not quite healthy people, as well as pregnant women. In many conditions, pressure must be constantly monitored, taking measurements several times a day. Although doctors recommend regular blood pressure monitoring for everyone who is about and over 40 years old. Thanks to this simple action, it will be much easier to maintain the health of your cardiovascular system and protect yourself from dangerous diseases such as heart attack and stroke.

Every 10 mm matters

Do not think that only huge pressure surges are dangerous. Studies have shown that an increase in this parameter by only 20/10 mm Hg. Art. increases the risk of developing cardiovascular diseases by 30%, and the risk of death in the presence of such diseases in this case doubles. People with uncontrolled high blood pressure are 7 times more likely to develop cerebrovascular accidents (strokes), 4 times more likely to develop coronary heart disease, 2 times more likely to develop vascular lesions in the legs.

Therefore, regularly monitoring and reliably knowing the level of your blood pressure is not a sign of a hypochondriac, but a habit of a person who is responsible for his health. But there is one “but”: only the right measurements will benefit.

If the readings of the device chronically show lower pressure numbers than they are, then this will not only not help a person to prevent a cardiovascular catastrophe, but will also not allow him to seek medical help in time, and, accordingly, the disease will progress. If, on the contrary, the tonometer regularly overestimates the readings, then there is a high risk of harming yourself by taking unnecessary medications to reduce pressure, which is also completely unsafe.

Why is he lying?

Most often, erroneous readings occur due to improper use of the device.

If we talk about mechanical blood pressure monitors, then errors in readings, as a rule, are explained by the lack of special training for users, and therefore they misuse the device. Also, the reason may be in the physical characteristics of the person making the measurement (for example, the presence of vision or hearing problems). The incorrect choice of the cuff, which does not correspond to the volume of the arm, also leads to distorted results. Even the smallest details are important for a correct measurement: for example, readings can fluctuate significantly if the cuff is inflated too slowly or too quickly, or if the cuff is worn too tight or on the arm over clothing. In addition, the readings of a mechanical tonometer - a device that is sensitive to room noise - may depend on the accuracy of the location of the stethoscope head relative to the artery. In general, using this device correctly is a whole science. Therefore, most people purchase automatic appliances for home use. But they also do not always give true results. No, the point is not at all that “mechanics” are more reliable than “automatic”. If the device is of high quality, it will work well in both cases. After all, it is not the design features of the device that are much more important, but its proper use.

By the way

Carpal automatic blood pressure monitors, which for some reason are considered by many to be less reliable and unsuitable for people over 45 years old, are in fact not inferior to conventional blood pressure monitors with a cuff on the shoulder (unless the wrist is at heart level when measuring).

What leads to erroneous pressure results

It is necessary to measure arterial (blood) pressure not only for hypertension or hypotension, but also for prevention purposes. You can carry out the procedure even at home. Special knowledge is not required. It is enough to purchase a tonometer and follow a simple algorithm of actions. The measuring apparatus can be automatic, semi-automatic and mechanical. The first 2 options are more convenient, but 3 is a more accurate device. It is able to perform its functions longer and does not require batteries. It is enough for a person to learn how to correctly measure pressure with a mechanical tonometer.

Each person could see how to measure pressure correctly while undergoing a medical examination. The procedure is quite simple and takes no more than 5 minutes. The obtained indicators are affected by the patient's age, weather, the presence of pathologies and body position, therefore, small deviations from the norm within 10-15 units are allowed.

Understanding how to measure your own blood pressure using a mechanical tonometer is quite simple if you familiarize yourself with the algorithm of actions below:

Having figured out how to measure pressure without leaving home, you can protect yourself from the development of hypertension or hypotension by periodically using a tonometer. To obtain more accurate data, it is advisable to remember the following tips:

• When measuring pressure on a large person, there are often problems with the size of the cuff. The forearm may be too large. In this case, you will have to purchase a device specifically for the individual characteristics of the structure or go to the hospital for measurement. In children, the situation is just the opposite. Their arm is too small, so you will have to buy a baby cuff.
• When performing the procedure on yourself or another person, you must be quiet and turn off third-party devices that make sounds in order to hear the tone.
• At least 3 minutes must elapse before repeating the measurement. The hand was pinched, so it takes time for it to return to normal. Otherwise, the figures will be overestimated.
• For convenience, the manometer can be hung on clothes when measuring another person or put on a table in front of your eyes.

• If it concerns children, then it will be necessary to carry out manipulations related to distracting the child from the procedure. In this case, you can eliminate the factor of excitement, which greatly distorts the final figures.

When measuring pressure, another person must independently hold the sound membrane and pressure gauge. The rest of the algorithm of actions is no different.

Get the most accurate results

A mechanical sphygmomanometer is considered the most accurate if blood pressure is measured correctly. For a person who decides to learn how to carry out the procedure at home, it is advisable to remember the following nuances:

• decide on a hand for taking measurements;
• see the list of the most relevant errors;
• prepare for the procedure.

Selecting a limb for measurement

An important nuance is the choice of hand. A person who wants to measure his pressure should not remember which limb the doctor put on the cuff. In any case, both limbs will be involved. Necessary:

• take 5 measurements on each hand with a break of 3 minutes;
• the results must be recorded;
• calculate the average value for each hand.

Focusing on the results obtained, it is necessary to make a choice in favor of more. For example, if the average values ​​are 118/78 on the right hand, and 125/80 on the left, then it is on the second limb that measurements should be taken. Sometimes the values ​​are not actually different. In this case, the rule of the main hand becomes relevant. Left-handers measure on the right limb, and right-handers on the left.

Most Common Mistakes

Despite the simplicity of the procedure, many people manage to make such mistakes:

1. improper preparation for the procedure (physical activity, drinking coffee, smoking a cigarette);
2. rolling up the sleeves of clothes;
3. measurement of pressure with an unsuitable cuff;
4. incorrectly selected position of the hand or the whole body as a whole;
5. too fast release of air when listening to noises;
6. non-observance of a break before re-measurement.

A doctor will never make such mistakes, but ordinary people do not pay attention to them, which is why incorrect pressure indicators are detected. To prevent missteps, it is necessary to carry out the procedure slowly, exactly follow the algorithm of actions.

Preparation for pressure measurement

A person who wants to know his blood pressure readings needs to prepare for the measurement. The following rules may help:

• do not smoke or drink alcohol 1 hour before the procedure;
• find a room where the temperature is from 23 to 26 °;
• go to the toilet before the measurement (if there is an urge);
• create a quiet environment in the room.

Even a child can correctly measure blood pressure with a mechanical tonometer if he follows the algorithm of actions and remembers the preparation rules and advice drawn up by specialists.

There is no particular difficulty in the procedure, but there are certain nuances that can distort the final indicators. They should be remembered and taken into account when measuring. If you have any questions, you can consult with a therapist or cardiologist. The doctor will explain in detail all the details of the process and tell you what mistakes to avoid.

You may also be interested in:

Apparatus for measuring pressure: typology and features

This is the pressure with which blood presses against the wall of an arterial vessel. It consists of 2 numbers: the upper (systolic) is the pressure on the vessel wall at the moment when the heart contracts, and the lower (diastolic) when the aortic valve is closed and the heart relaxes and rests. Systolic pressure is determined by cardiac output, and diastolic pressure depends on how spasmodic or dilated the vessels are, that is, on their tone. Blood pressure up to 140/90 mm Hg is considered normal. Anything above is arterial hypertension, the most common complication of which is a stroke or heart attack.

You decided to measure the pressure, but it turned out to be elevated. Immediately start taking pills, call children or call an ambulance.

In fact, it may be normal, you just made a mistake when measuring.

First rule. Sit, lean back in a chair, relax, place your arm bent at the elbow on the armrest or on the table so that it is at the level of the heart, and apply the cuff 2-3 cm above the fold. Tension and excitement increases blood pressure by 10 mm Hg. In no case should you measure blood pressure while standing or holding your hand on weight.

Secondly It is not recommended to measure blood pressure through clothing, especially thick clothing. The cuff first compresses the clothes and only then the vessels, therefore, blood pressure rises. Because of this, its maximum increase can be up to 40 mm Hg. The thicker the clothes, the higher the blood pressure.

The third mistake in determining blood pressure- Wrong posture. You sat down, crossed your legs, you feel comfortable, but the vessels of the lower extremities are compressed, they narrowed, blood pressure increased by another 8-10 mm Hg.

If you have made all of the above mistakes, then in total this will give an increase to your true pressure of 50-60 mm Hg. You think that you have high blood pressure, you are nervous, you are taking medicines that you do not need at the moment, but it is actually normal.

How to measure blood pressure correctly?

Do not forget, that pressure should be measured silently, without talking, being in a calm state, since when talking, muscles tense up, their tone rises and blood pressure also becomes 15 mm Hg higher.

It is impossible to measure the pressure with a full bladder, as when holding urine, blood pressure rises. After going to the toilet - minus 15 mm Hg. You also need to remember that, being in a cold room, we add + 20 mm Hg to normal numbers.

Therefore, before you are going to measure blood pressure, so that its numbers are objective, just go to the toilet, sit in a warm room, relax, lower your legs, roll up your sleeve and then your blood pressure will not be higher than 140/90 mm Hg.

With care for your health,

Today there is an electronic blood pressure monitor in almost every home. This is an obligatory attribute of a first-aid kit in the elderly, and young people have begun to massively acquire this medical device. However, not everyone knows how to use it correctly. Hence the talk about inaccurate electronic blood pressure monitors, and other misconceptions about blood pressure. MedAboutMe looked into the most common mistakes people make when taking their own blood pressure.

For the first time in the history of mankind, blood pressure (BP) was measured by Stephen Hales in 1714. The experimental animal was a horse, in the carotid artery of which the researcher inserted a vertical brass tube and watched to what height the column of blood rises. Over the next 200 years, a whole galaxy of scientists came up with different ways to measure pressure and created various devices, until, finally, in 1905, our compatriot, military surgeon N.S. Korotkov did not develop a sound method for measuring blood pressure, which is also called auscultatory. This method has been used for more than 100 years in mechanical (manual) tonometers.

The essence of the Korotkov method is as follows: a cuff (Riva-Rocci sleeve, named after its inventor) is put on the patient's shoulder and air is injected into it. The air pressure in the cuff is monitored by a manometer, which is carefully looked at by the doctor. In this case, the stethoscope (or phonendoscope in later versions) is placed on the projection of the brachial artery in the fossa of the elbow. What is happening?

1. Air is pumped into the cuff until the pressure in the cuff is higher than the person's systolic pressure. This moment is easy to determine: the doctor stops hearing any sounds. The blood flow is completely blocked.
2. Then the doctor begins to gradually bleed the air from the cuff, and the pressure in it drops. As soon as it becomes equal to the systolic pressure of a person, the doctor hears the so-called first Korotkoff tone. At the moment of systole, the pressure in the brachial artery increases, and the blood passes jerkily through the vessels of the shoulder. Therefore, sounds and noises are uneven.
3. The doctor continues to bleed air, the pressure in the cuff drops even lower, the sound in the phonendoscope becomes muffled - and disappears completely. At this point, diastolic pressure is recorded. As soon as the pressure in the cuff falls below this value, it means that there are no more obstructions to the blood flow.

Mechanical blood pressure monitors are inconvenient because a person must have certain skills to use them. As a result, the human factor plays too large a role in measuring pressure using the Korotkoff method.

Therefore, electronic tonometers, which are based on the oscillometric method of measuring blood pressure, have gained such popularity. The essence of the method is to register changes in tissue volume during arterial pulsation, depending on the dosed pressure exerted on the limb. That is, the equipment reads changes in cuff pressure that are invisible to the eye. This technique was first proposed by the physiologist E. Marey in 1876. At that time, it was too complicated. Today, humanity has acquired computers and analytical programs that allow you to calculate data of any bulkiness. We also add that, unlike tonometers using the Korotkoff method, electronic tonometers make it possible to apply a cuff even to a thin layer of tissue. The error of modern electronic tonometers does not exceed 3 mm Hg. Art.

True, with home use, the influence of the human factor cannot be avoided anyway. What mistakes do ordinary patients who want to measure pressure on their own make?

Mistake #1. Incorrect cuff selection

Carpal electronic tonometers and shoulder ones are sold in stores. The first, as you might guess from the name, are worn on the wrist. But they have a number of limitations. Carpal tonometers are not recommended for use:

• Obese people, since their pressure indicators are very dependent on how far from the heart the tonometer will be. In addition, in overweight people, the diameter of the vessels is a variable value. Therefore, the risk of obtaining incorrect indicators is high.
• People over 45, as blood vessels lose elasticity as they age.

So, when trying to use carpal tonometers for these categories of people, the probability of an incorrect indicator is very high. If the blood pressure monitor is purchased for the family, and not for a specific person, it is better to immediately buy the version with a shoulder cuff so that it can be used for all family members.

Mistake #2. Wrong cuff size

This is the most common error in measuring blood pressure. It is necessary to select the cuff based on the circumference of the person's shoulder. In an adult, this indicator is in the range of 23-32 cm. Too large a cuff will lead to an underestimation of blood pressure, and too short and narrow, on the contrary, will overestimate them.

American cardiologists recommend that the length of the inflated part of the cuff (pneumatic chamber) be at least 80% of the circumference of the arm, that is, approximately 18-26 cm. The width of the cuff should correspond to approximately 40% of the circumference of the arm, that is, equal to see. You can estimate the size of the cuff "by eye": it should cover 2/3 of the distance from the elbow to the person's shoulder.

The blood pressure monitor comes with a cuff for the average adult. If the arm circumference is significantly larger (or smaller), then you need to take care of purchasing a special cuff of the appropriate size.

Mistake #3. Incorrect body position

To accurately determine blood pressure, it is necessary to eliminate the influence of gravity as much as possible. Traditionally, blood pressure is measured at the level of the heart. At the same time, the vertical position of the body provides the most accurate indicators. Lying on your side or other postures create additional interference. You can put the patient on his back, but in this case, the limb should be at the level of the heart. In addition, the indicators at the same time increase by 3-5 mm Hg. If the cuff is higher than the heart, blood pressure will be lowered. If it is lower, on the contrary, it is too high. The error can be quite significant: every 2-3 cm up or down from the level of the heart give, respectively, minus or plus 2 mm Hg. Art.

Cardiologists talk about the so-called phlebostatic axis, passing approximately through the junction of the IV rib with the sternum - at this level the middle of the right atrium chamber is located. It is she who should be guided as the “heart level” when measuring blood pressure. Doctors point out that in people with kyphosis or chronic obstructive pulmonary disease (COPD), this axis can be shifted, so self-measurement of pressure in such patients can lead to erroneous readings.

So, the correct position: sitting on a chair with a back, the hand lies freely on the table with emphasis in the elbow area. During the measurement, you can not move your hand, you can not even speak.

Mistake #4. Incorrect cuff placement

When measuring blood pressure, thick clothes must be removed: a sweater, a jacket - all this will degrade the accuracy of the measurement. When using electronic blood pressure monitors, the cuff can be placed directly on the shirt. Legs should not be crossed or thrown knee over knee - this leads to an increase in systolic blood pressure by 2-8 mm Hg. Art.

Interestingly, you can measure pressure in different parts of the arms and legs - at the wrists, on the toes, at the ankles, and the results will vary depending on the distance to the heart. The farther away from the heart is the area where the pressure is measured, the greater the systolic pressure and the lower the diastolic. In this case, the average indicator changes little.

In every fifth person, the difference in blood pressure between the right and left arms is more than 10 mm Hg. Art. In this case, the choice is always made in favor of large values.

Mistake #5. Attempt to measure the pressure several times

One of the most popular mistakes is trying to measure the pressure several times, and even on the same arm. The results obtained lead a person to the idea of ​​a defective tonometer or that all electronic tonometers are lying. And the fact is that the vessels have time to adapt to decompression at the first measurement. Therefore, the second and subsequent attempts to measure pressure give completely different results than the first: the numbers may differ by 20-40 mm Hg. Art. Therefore, it is so important to follow the instructions and take repeated measurements no earlier than after 7-10 minutes.

To a large extent, the pressure of a person depends on what he did before the measurement. Therefore, a number of rules should be strictly observed, taking into account the psychology of the patient:

• It takes 5-10 minutes for a person to adapt to the doctor's office. "White Coat Syndrome" is one of the main problems of blood pressure measurement in conventional clinics. Hidden fear of doctors is reflected in elevated blood pressure.
• An attempt to take the pressure immediately after coming from the street or in a state of excitement adds 20 to 40 mm Hg. Art.
• Talking during the measurement can "throw" another 10 mm Hg. Art.
• The last cigarette before measuring pressure should be smoked at least 1.5-2 hours before.
• At least one hour before the procedure, you should not eat, and two hours is the minimum interval after drinking alcohol, tonic drinks.
• After taking eye and nasal drops, 1.5-2 hours should also pass.

And the last important point. If there is a suspicion that the tonometer is "jumping" - check the batteries or try switching to the power supply. It is possible that the reason for the “jumps” in blood pressure lies precisely in this.