Which arm is used to measure blood pressure?

According to statistics, 40% of the population has high blood pressure from time to time . People who have not experienced such problems before may not attach much importance to symptoms such as headache, heaviness in the back of the head, nosebleeds. But these are exactly the signs, because of which it is necessary to check the systolic and diastolic indicators on the left hand.

What tonometer to measure?

There are several factors to consider when choosing. If the device is needed only for prevention purposes, the simplest model will do. For those who have cardiovascular pathologies and are undergoing treatment, it is better to choose a more accurate device.

There are three types of devices for measuring blood pressure on the walls of blood vessels:

• automatic;
• mechanical;
• semi-automatic.

The most common are mechanical tonometers.

They are easy enough to measure on both hands and feet. Consist of a cuff, a rubber pear, a monometer. The set also includes a phonendoscope. During the measurement, the cuff is put on the forearm, a phonendoscope is applied near it, and the air outlet is blocked on the pear. When you press the rubber element, air enters the cuff, the vessels on the arm are compressed. After that, an air outlet opens on the pear and during this process, the initial and final pulse can be heard through the phonendoscope.

This will be the upper and lower pressure. But using a mechanical instrument takes practice. Not everyone succeeds in measuring correctly the first time. An automatic blood pressure monitor is considered the most convenient. It does not require any involvement. The device itself pumps air, and determines the performance. It is enough to put the cuff on your wrist or forearm, turn on the device and wait a few seconds until the result appears on the screen.

Although the numbers will be determined quite correctly, such a device also has significant drawbacks: the electrical part very often fails, and the batteries will constantly have to be changed. Semi-automatic tonometer partly resembles automatic and mechanical. The difference lies in the fact that in such a device, air is manually injected into the cuff, that is, you need to press the pear, but the device displays the indicators on the screen on its own.

How to measure pressure correctly?

For the most accurate determination of systolic and diastolic indicators, it is necessary that the person is in a comfortable position. Sit comfortably in a chair and relax.

An hour and a half before the procedure, you can not drink tea, coffee, alcohol and smoke. These factors greatly influence the data. The hand should be positioned correctly. It is best if it is on the armrest, the muscles should be as relaxed as possible.

And you need to do this several times with an interval of two minutes. After that, you need to determine the average. It is he who will be the most accurate.

Particular attention should be paid to the difference between the results. If the discrepancies are from 10 millimeters of mercury and above, this may indicate the presence of pathology. When a large difference is observed in the measurements on the left hand, this indicates diseases of the lungs, heart, and blood vessels. On the right - about problems with the liver, stomach, intestines.

To get the most reliable result, you should:

• sit quietly for at least five minutes before the procedure;
• correctly measure at a temperature not lower than +20 and not higher than +25;
• do not cross your legs during the procedure;
• lean back against the back of a chair;
• measure not earlier than one hour after eating.

To do this, you will need to perform the following steps:

1. Fix the cuff on the left arm.
2. A phonendoscope membrane is applied in the area of ​​the cubital fossa.
3. The pointer on the meter must be at zero.
4. The air outlet is blocked in the pear, and the cuff is inflated. It is necessary to pump air until the arrow on the dial rises a few points above the expected values.
5. After that, the air must be slowly released.
6. The first sounds of the pulse are the value of systolic blood pressure. The latter is the number of diastolic blood pressure.

The measurement process with an automatic and semi-automatic tonometer does not differ much. The difference lies in the fact that in the first case, the device does not require human participation at all, and in the second case, you need to pump the air with your own hands, and the device gives out the indicators itself.

If during the measurement process on the left hand the tone is poorly heard, you need to raise the limb and bend and unbend the arm several times. After that, during the next procedure, the tremors of blood will be heard better.

In the case when the blood pressure is greatly increased, the pressure is also measured on the legs. The person lies on his stomach, the cuff is located on the thigh in such a way that it is slightly above the knee. On the legs, the correct location of the tonometer is that the center with the tubes is above the femoral vein, and the sound amplifier of the stethoscope is under the knee. But when measuring, it should be borne in mind that systolic pressure in the legs is higher than in the arms.

Pressure Measurement Methods

Manometry can be direct or indirect. In the first case, measurements take place in a vessel or cavity of the heart using a capillary. Since this method requires surgical intervention, it is carried out only in a hospital.

The second option, compression, allows you to find out blood pressure indicators by balancing the strength of the blood flow inside the vein through the tissues of the body. This method can be carried out in any conditions. This measurement technology was recommended by the Italian physician Riva-Rocci back in 1896. Compression using a Recklinghausen cuff was carried out by applying it around the upper limb. As a result, uniform compression of the tissues and blood vessels that were inside it was ensured.

A cuff measuring about 14 centimeters was worn on the forearm. It quickly pumped air to a value exceeding the expected systole. After that, the air was gradually released, the occurrence of pulsation in the radial artery was recorded by palpation, and this time was noted on the manometer. Over a long period, the increase in blood pressure was established by palpation of a vein in the left arm.

In 1905, Nikolai Sergeevich Korotkov, a St. Petersburg surgeon, discovered the auscultatory method for diagnosing high blood pressure. He found that when external pressure is applied to a vein, sounds appear in it, which disappear when it exceeds systolic pressure. Listening to the brachial artery during its decompression made it possible to determine the moments of the onset and end of sounds, and the indicators corresponding to this time were noted on the pressure gauge.

N. Korotkov identified four stages of sound manifestations during the determination of blood pressure:

The first occurrence of tones. Parameter (upper) systolic index. At a certain moment, the pulse waves overcome the resistance of the compressive material and stretch the veins. The force of blood pressure in systole is greater than the air in the cuff, and its first amount, entering the cavity below the constriction point, causes the relaxed walls of the empty vein to oscillate.

The occurrence of compression noise. During the release of air from the device, compression noises occur, which depend not only on the movement of blood below the squeezing site, but also on the degree of impact on the blood vein.

The emergence of loud tones. In the process of reducing the pressure of blood, the noises again change to tones. This is due to the fact that the pressure in the cuff continues to decrease and, accordingly, the artery returns to its original state, more blood enters the vein, and the oscillation of its wall increases. Sounds reappear.

Loss of tones. After the sounds reach their maximum, they become quieter, and subsequently completely disappear. This moment corresponds to the diastolic pressure.

The disadvantage of this method is its sensitivity to noise in the room and the accuracy of the placement of the phonendoscope (experience is required). In 1962, the World Health Organization recommended the Korotkov method as the most appropriate for use in medical practice.

Oscillometric method is used not so long ago. It is based on fixing with an electrical device the air pressure pulsations that occur in the cuff during the passage of blood through the squeezed section of the vein. This method does not require practice and does not depend on the person conducting the measurement. But in order to measure correctly, the arm must be completely motionless during the procedure.

What should be the blood pressure?

It increases significantly with nervous excitement, physical work, after eating, strong coffee. Such reasons relate, as a rule, to the systolic index.

The lowest numbers on the tonometer can be seen in the morning, at rest, on an empty stomach. When systolic pressure exceeds 140 mm Hg. Art., and diastolic more than 90 mm Hg. Art. diagnosed with arterial hypertension.

During pressure measurement, the following errors can be made:

1. The ratio of cuff length and arm width is not taken into account.
2. The cuff can be re-inflated only after the air is completely released from it.
3. Improper preparation of the patient.
4. The stress reaction of the body to the measurement process itself can increase the pressure.

When the systolic pressure is less than 100 mm Hg. Art., and diastolic - no more than 60 mm Hg. Art., hypotension is diagnosed. The difference in arterial parameters of the left and right hands in a healthy person should not be more than 5 mm Hg. Art. This number depends on the parameter of the subclavian vessel origin, the level of wall density. Blood pressure in the legs, popliteal vein, an average of 30 mm Hg. Art. more than on the shoulder.

If you measure the pressure on the arm correctly and regularly, this will allow you to control your health and identify disorders in the cardiovascular system at an early stage. Any deviations from the established norm require the establishment of a cause, that is, a medical examination.