How to choose a blood pressure monitor? What should I pay attention to when taking my blood pressure? How often should I take a blood pressure test?

How to choose a sphygmomanometer

There are three types of sphygmomanometers in common use: mercury column sphygmomanometer (mercury column sphygmomanometer, cuff sphygmomanometer), barometer sphygmomanometer and electronic sphygmomanometer.

The mercury sphygmomanometer is the best choice because of its high accuracy and reliability. The mercury must be in sufficient quantity when used, and the switch must be turned off after use, so that the mercury does not leak out. The sphygmomanometer operator should be qualified and trained.

Barometer sphygmomanometers (also known as non-fluid sphygmomanometers) are not as accurate as mercury-column sphygmomanometers, and should generally be calibrated with mercury-column sphygmomanometers once every 6 months.

Electronic sphygmomanometers are lighter, easier to carry and operate, and should be as accurate as traditional mercury-column sphygmomanometers if used correctly. However, it is affected by conditions, such as surrounding noise, cuff movement and friction, and other factors, the measured blood pressure and the actual blood pressure has an error, therefore, it must be frequently calibrated with the mercury column sphygmomanometer. The cuff type is the best, the wrist type is the second best, and the finger cuff type is the least recommended.

How to Measure Blood Pressure

Rest for 5 to 10 minutes in a quiet environment, in the supine or sitting position.

The upper limb to be measured (usually the right upper limb) is bare, the elbow should be at the same level as the heart, and the upper arm is straight and mildly abducted.

The airbag part of the cuff is aligned with the brachial artery, and it is tightly bound to the skin on the upper arm, and the lower edge of the cuff should be 2-3 cm from the transverse stripe of the elbow.

The examiner should first palpate the arterial pulsation at the elbow socket, and then place the stethoscope chest piece at the brachial artery at the elbow socket, and gently press the chest piece of the stethoscope and the skin to closely connect it, but not to be pressed too hard, not to come into contact with the cuff, and even more not to be tucked under the cuff.

Inflate the cuff, inflate and auscultate, wait for the brachial artery pulsation to disappear, and then raise the column 20 to 30 mmHg, start to slowly deflate, and look at the column with flat eyes to slowly decline.

The first sound heard when the column value for the systolic blood pressure, with the column down, the sound gradually strengthened, followed by the emergence of blowing-like murmur, and then the sound suddenly became small and low, and ultimately the sound disappeared, at this time, the mercury column value for the diastolic blood pressure.

What to pay attention to when measuring blood pressure

Because blood pressure has the characteristic of obvious fluctuation, it is necessary to repeat the measurement several times on a non-same day in order to judge whether the increase in blood pressure is persistent.

The environment should be quiet; rest quietly for at least 5 minutes; no smoking or drinking coffee and empty the bladder for 30 minutes before the measurement; the patient should be as relaxed as possible, preferably in a reclining chair; and the right upper arm should be exposed, with the elbow placed at the same level as the heart.

Measuring tools should be standardized, and the cuff size should meet the requirements. The airbag in the cuff should wrap at least 80% of the upper arm, most people's arm circumference of 25-35cm, it is appropriate to use a wide 13-15cm, 30-35cm long specification of the airbag cuff, the obese or arm circumference should use a large specification of the cuff, and the children use smaller cuffs.

The method should be appropriate, and the measurements should be repeated 1 to 2 minutes apart, with the average of the two readings recorded. If the difference between the systolic or diastolic readings of the 2 measurements is >5mmHg, it is necessary to measure again and then take the average of the 3 readings. It is more difficult to measure blood pressure accurately when the heart rhythm is irregular, especially in the case of frequent premature beats or atrial fibrillation, and it is necessary to take the average of 6 repeated measurements of blood pressure to minimize the error.

How often should you measure your blood pressure?

Because all kinds of activities and emotional changes can significantly affect the blood pressure, patients who are in a position to do so can measure their own blood pressure on a daily basis.

Mild and moderate hypertension or severe hypertension patients whose condition has been stabilized can have their blood pressure checked every 3 to 7 days when they start treatment, and once every half a month or so after their blood pressure is controlled, or once a month for those with milder conditions. For patients with severe disease and rapid changes, measuring blood pressure 1 to 2 times a day is sufficient. For critically ill patients with rapid changes in blood pressure, blood pressure should be measured every few minutes to tens of minutes.

What are the causes of large fluctuations in blood pressure

Electronic sphygmomanometers have large errors and should be calibrated regularly with a standard mercury column sphygmomanometer. The mercury column sphygmomanometer must have a sufficient amount of mercury, the concave surface of the mercury in the graduated tube should be exactly at the scale?0? point, and the switch of the mercury column should be opened before use and closed after use.

Incorrect measurement method: the position of the upper arm is higher than the level of the heart, which can make the measured blood pressure value lower than the actual, on the contrary, the measured value is higher than the actual. The sphygmomanometer should be placed directly in front of the person taking the measurement, with both eyes looking down at the changes in the mercury column; it is not easy to read the blood pressure values by looking down and looking up. Do not measure blood pressure continuously, there should be a moment's rest between each two measurements, so that the blood flow in the upper arm to return to normal, and at the same time, it is desirable to deflate slowly, otherwise the error will be too large.

Atrial fibrillation and other arrhythmia patients, each time the heart's beat volume is not equal, in the measurement of blood pressure, different time can be different values, so should be measured several times, take its average value.

Inappropriate size of the airbag: If the cuff is too wide, the measured blood pressure is lower than the actual, and if the cuff is too narrow, the measured blood pressure is higher than the actual. Therefore, the cuff should be divided into those for children and those for adults, and separate the cuffs for the upper and lower extremities.