The level of blood pressure is a barometer of physical health. In life, there are always people who ask the question: I am nervous when I enter the hospital, and I shiver when I see the doctor. Every time I have a medical checkup, my blood pressure is high, but when I go home, it is normal again ……
In this case, which blood pressure is true and which is false? How to reduce these misunderstandings, so that we can accurately and comprehensively understand their blood pressure status?
Don’t worry, “Ambulatory Blood Pressure Monitoring” is the answer!
Ambulatory blood pressure monitoring – unlocking new blood pressure measurement skills
Ambulatory blood pressure monitoring refers to a diagnostic technique that automatically, intermittently and regularly measures the blood pressure value in daily life through an instrument.
1.Correct operation
To perform ambulatory blood pressure monitoring, you first need to choose a suitable blood pressure monitor. It is recommended to choose an ambulatory blood pressure monitor that has been independently clinically validated according to international standard protocols and has met the accuracy requirements, such as the oscillometric upper arm ambulatory blood pressure monitor.
Once the equipment is ready, the arm circumference is measured and the appropriate size sphygmomanometer cuff is selected according to the arm circumference. As with in-office blood pressure measurements, most adults usually choose a standard cuff, while those who are obese and have a large upper arm circumference (≥32 cm) should choose a large cuff and those with a small arm circumference (<4 cm) should choose a small cuff.
After wearing the sphygmomanometer, two manual measurements with the ambulatory sphygmomanometer are usually taken first to test whether the sphygmomanometer is working properly. At the end of monitoring, two more manual measurements are taken with the ambulatory sphygmomanometer before removing the sphygmomanometer to confirm that the sphygmomanometer is working properly.
Subsequently, the measured person can use the diary card to record the daily routine on the day of blood pressure monitoring, including waking up, sleeping, lunch break, three meal times as well as activity and medication information, which will help to write the ambulatory blood pressure assessment report later.
2.Result determination
How is hypertension determined by ambulatory blood pressure monitoring?
The ambulatory blood pressure criteria for the diagnosis of hypertension are specifically 24-hour average systolic/diastolic blood pressure ≥ 130/80 mmHg, or daytime ≥ 135/85 mmHg, or nighttime ≥ 120/70 mmHg.
It is important to note that early morning hypertension is diagnosed if the early morning blood pressure is ≥135/85 mmHg, regardless of whether or not the person is receiving antihypertensive medication.
Since the ambulatory blood pressure index used to diagnose hypertension consists mainly of the average of the systolic and diastolic blood pressure of all blood pressure readings over 24 hours, daytime and nighttime. It is generally recommended that the person being measured define daytime and nighttime by the time of awakening in the morning and going to sleep at night as recorded on the ambulatory blood pressure monitoring diary card.
Ambulatory blood pressure monitoring – a boon to those with abnormal blood pressure
Clinically, ambulatory blood pressure monitoring has four main applications, including diagnosing hypertension and improving the accuracy of hypertension diagnosis; assessing the risk of cardiovascular disease and improving the level of risk assessment; assessing the effectiveness of antihypertensive treatment; and guiding individualized treatment of hypertension and improving the quality of antihypertensive treatment.
Like a personal bodyguard, it does not interfere with the normal life and work of the measured person, silently monitors and records the blood pressure throughout the day, perfectly realizing 24-hour blood pressure control, giving full play to the advantages and usefulness of antihypertensive treatment to prevent cardiovascular and cerebrovascular complications.
1.It can distinguish “white coat hypertension” and “hidden hypertension” with a sharp eye
White coat hypertension is a condition in which the blood pressure of the person being measured is elevated when the blood pressure is measured in the doctor’s office, but the blood pressure is normal when no medical personnel are present. Covert hypertension has the opposite threshold and refers to normal blood pressure measured in the doctor’s office and elevated blood pressure measured during normal hours.
In contrast to office blood pressure measured in a physician’s office, 24-hour ambulatory blood pressure monitoring can diagnose white coat hypertension and covert hypertension that are not yet receiving antihypertensive medication, as well as white coat uncontrolled hypertension and covert uncontrolled hypertension that are receiving antihypertensive medication.
Compared with home blood pressure measured by yourself at home, 24-hour ambulatory blood pressure monitoring is also more sensitive for the diagnosis of covert hypertension and white coat hypertension.
2.It can target the blood pressure at special times like a fixed and detailed view
Blood pressure at special times mainly refers to early morning hypertension and nighttime hypertension. Among them, early morning is the high incidence of cardiovascular events, the peak incidence of myocardial infarction, sudden cardiac death and stroke are 4-6 hours before and after waking up.
Patients with pure nocturnal hypertension tend to have elevated blood pressure at night and normal blood pressure during the day. These patients have an increased risk of target organ damage and cardiovascular events compared to those with normal blood pressure.
Ambulatory blood pressure testing monitors blood pressure fluctuations in youth and during nighttime sleep, and provides regular, accurate measurements and blood pressure profiles at night. It is significantly superior to office blood pressure and home blood pressure.
3. It can detect circadian rhythms and short term variation in blood pressure
Usually, blood pressure in the physiological state will show a more obvious circadian rhythm, that is to say, blood pressure during the sleep period is significantly lower than during the waking hours of the day, in the early morning hours from sleep to awakening, blood pressure is obviously rising trend.
Ambulatory blood pressure monitoring can accurately record blood pressure values throughout the day, identify abnormal blood pressure patterns, detect circadian rhythms and short-term variations in blood pressure, and help optimize the antihypertensive treatment plan for hypertension according to the patient’s blood pressure circadian rhythm.
In addition, because the white coat effect is common in patients with suspected refractory hypertension, the clinic can also distinguish between true and pseudo-refractory hypertension based on ambulatory blood pressure monitoring results.
Currently, ambulatory blood pressure monitoring has become an indispensable test for identifying and diagnosing hypertension, assessing the risk of cardiovascular and cerebrovascular diseases, evaluating antihypertensive efficacy, and guiding individualized antihypertensive treatment. Ambulatory blood pressure monitoring can be applied at the recommendation of physicians for newly identified patients with grade 1-2 office hypertension, as well as for hypertensive patients already receiving antihypertensive therapy.
References
[1] Committee on Ambulatory Blood Pressure Monitoring Guidelines of the Chinese Hypertension Consortium.2020 Guidelines for Ambulatory Blood Pressure Monitoring in China [J]. Chinese Journal of Circulation,2021:04(36):313-319.