Regarding blood pressure measurement, there are three issues that everyone is most concerned about

The importance of taking blood pressure has been mentioned many times in the health headlines before. In addition to paying attention, it is more important to measure blood pressure accurately.

I have previously told you about the posture of blood pressure measurement and the precautions before blood pressure measurement. Click here to learn more.

In addition to these... there are many questions:

Is the electronic sphygmomanometer accurate?

Why is the left hand and right hand different?

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Let's answer everyone's questions again, hoping to be helpful to you.

What kind of sphygmomanometer should I choose?

Current sphygmomanometers mainly include desktop mercury sphygmomanometers and medical automatic electronic sphygmomanometers. For patients monitoring blood pressure at home, electronic sphygmomanometers are now recommended.

There are two reasons:

The use of electronic sphygmomanometers is simple: mercury sphygmomanometers are relatively complex to use, difficult to complete by one person, and greatly influenced by the subjective impact of measurement personnel; The medical automatic electronic sphygmomanometer validated by international standards can automatically provide systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, and measurement time, which is simple to operate and reduces measurement errors caused by human subjective factors.

Mercury is hazardous: The mercury in a desktop mercury sphygmomanometer can be harmful to the human body and the environment, so special attention should be paid to the leakage of mercury when using it. Cleaning and calibration should be carried out at least every six months. The electronic sphygmomanometer does not have the problem of mercury leakage.

Regarding accuracy, current research has not found any significant differences in accuracy between the two. As long as the correct use method is mastered, electronic sphygmomanometers are more suitable for use at home. At the same time, more and more medical institutions are also using electronic sphygmomanometers for monitoring.

When purchasing electronic sphygmomanometers, please pay attention to whether there are certification standards. Currently, the international certification standards include the British Hypertension Society (BHS) and the American Association for the Advancement of Medical Devices (AAMI).

Why are the left and right hands different?

The shape of a person's blood vessels is not completely consistent on both sides. As for the arteries measured by the upper arm sphygmomanometer, we measure the brachial artery. The brachial artery on the right is the first branch of the aorta, and the brachial artery on the left is the third branch. When blood travels to the left, it consumes more energy than the right, so the blood pressure of the average person on the left is lower than on the right.

The difference between the left and right sides is generally between 5 and 10 mmHg, and about 20% of normal people have a blood pressure difference of>10 mmHg between the left and right upper arms. Therefore, it is recommended to measure the blood pressure of the left and right upper arms during the first examination. When the blood pressure of the left and right upper arms is inconsistent, the blood pressure measured on the arm with the higher value shall prevail.

However, if the blood pressure difference between the two sides continues to be more than 20 mmHg, there may be vascular diseases, such as narrowing of the aortic arch and occlusion of the upper limb arteries, arteritis, arterial malformations, severe atherosclerosis, aortic dissection involving the subclavian artery, etc. If this happens, you should go to the hospital in a timely manner and ask the doctor for further examination to clarify the cause.

Sit and measure? Lie down and measure?

There are reports that the diastolic blood pressure measured in the sitting position is 5 mmHg higher than that in the supine position, and the systolic blood pressure measured in the supine position is 8 mmHg higher than that in the upright position. Moreover, various reports vary, and no clear and meaningful differences have been found at present.

Therefore, the current guidelines do not specify whether to sit or lie down for blood pressure measurement. It is generally believed that when measuring blood pressure, as long as the patient's measured upper arm is at the heart level, they can take a sitting position, a lying position, or even a standing position as needed.

For convenience, most clinical patients use a sitting position. It is recommended that everyone also try to monitor the blood pressure in the sitting position.