Do you know how to use a blood pressure monitor correctly and how to measure blood pressure?

Do you know how to use a blood pressure monitor correctly and how to measure blood pressure?
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Until recently, the blood pressure monitor was a professional device used exclusively by doctors. Now, however, it has made its way into the home of almost every layman. Regular blood pressure measurement in patients with arterial hypertension is of great benefit. Who should measure their blood pressure, when and how?

Are you the owner of a blood pressure monitor? Are you being treated for arterial hypertension, do you have a family history of this disease? Do you suffer from other diseases that can affect your blood pressure values?

It's good to know what blood pressure is to begin with

Blood pressure is the hydrostatic pressure exerted by blood circulating in the vasculature on the inner wall of blood vessels.

It is also an important variable, reflecting the state of the body's internal environment.

We can express blood pressure values numerically in torr. The older name for torr is mmHg (millimetres of mercury column). This old name is derived from older pressure gauges using mercury.

The upper (systolic) pressure is determined by the force of the contractions of the heart chambers.
The lower (diastolic) pressure is the pressure that persists in the blood vessels after the heart chambers have relaxed.

The normal blood pressure value for an adult is 120/80. The value of 120 torr represents the upper (systolic) pressure, the second value (always lower) of 80 torr represents the lower (diastolic) pressure.

Blood pressure is a parameter that is influenced 24 hours a day by external and internal factors.

Its fluctuations during the day are pronounced, for example, during sports, arguments, crying...

What are the physiological values of blood pressure?

The physiological value of blood pressure varies according to age. It is also influenced by the patient's current condition or associated diseases.

Read also the article in the magazine:
Summary table: what are the values of low, normal and high blood pressure?

For example, a blood pressure of 120/80 would already be high for a newborn.
An adult, on the other hand, would collapse at neonatal values.
Do not expect to have tabular blood pressure values after physical or mental exertion. Higher values are normal after exertion.

Table of blood pressure values by age

Period Approximate blood pressure value
Newborn period 80/50
Infant period 90/60
Toddler period 95/65
preschool age 105/70
School age 110/75
adolescence (puberty) 115/80
Adulthood 20-40 years 120/80
Adulthood 40 to 60 years 130/85
Age 135/85

What is a blood pressure monitor?

A pressure gauge or the older name manometer is a device for measuring pressure in general (blood pressure, gas pressure, atmospheric pressure, tire pressure).

A pressure gauge for measuring blood pressure is professionally called a sphygmomanometer.

It consists of a measuring unit and an inflatable cuff with an inflation mechanism. Mercury pressure gauges also require a stethoscope for measurement.

Table with basic division of pressure gauges

Manual pressure gauge Digital pressure gauge
  • Mercury pressure gauge
  • Mechanical (aneroid) pressure gauge
  • shoulder pressure gauge
  • wrist pressure gauge

Manual Pressure Gauge

Manual blood pressure monitors require a stethoscope (phonendoscope) to measure pressure.

Their operation is more complicated for ordinary people. Therefore, they are classified as primarily medical, professional blood pressure monitors, but they can also be used by experienced lay people.

There are two types of manual blood pressure monitors in use. The first is the older mercury column pressure monitor. More often, however, you will come across a newer aneroid blood pressure monitor based on a metal element that senses blood pressure.

  1. The mercury blood pressure monitor is a traditional pressure gauge that uses harmful mercury to measure blood pressure. Because of this, they can no longer be used in some countries, but are still found in some households. It is one of the most accurate measuring devices ever. The downside is the difficulty of maintaining the blood pressure monitor and the possibility of mercury leakage. Some doctors still mourn the ban on mercury blood pressure monitors today.
  2. The aneroid pressure gauge is the new equivalent of pressure gauges after the ban on mercury devices. The calibres of aneroid pressure gauges (without fluid) are based on a metal element that senses the pressure. The pressure sensing element can be a Bourdon tube, a diaphragm or a capsule that changes shape depending on the pressure. The pressure is read from a dial. Today it is the most accurate pressure gauge allowed in the EU.

Interesting:
Mercuryis a harmful metal that has a negative impact on living organisms, including humans, as well as on the environment.
It evaporates when spilled. There is a risk of unknowingly being absorbed into the body through the respiratory tract.
Prolonged exposure to mercury or higher concentrations of mercury can damage the liver, kidneys or nervous system.
It endangers pregnant women and harms the unborn foetus (developmental defects, fetal malformations).
The European Union therefore bans the marketing of mercury pressure gauges, or any device containing mercury (thermometer).
Exceptions include only those devices for which we do not yet have a suitable replacement.

Digital pressure gauge

The most modern variation of pressure gauges are digital (electronic, battery-operated) pressure gauges.

They measure pressure based on oscillometric detection. They use deformable diaphragms that can change their shape.

They have advantages that modernisation brings with it. These include ease of use for the layperson, absence of a stethoscope, digital display as an indicator of the measured value, etc.

Unfortunately, the disadvantage of these devices is that the measured value is less accurate.

Factors such as weak batteries, poor calibration of the device, tremor, shivering, arrhythmia, atherosclerosis, pre-eclampsia, pulsus alternans, etc. also distort the result.

  1. Shoulder Pressure Gauge - The gauge cuff is placed on the shoulder of the left upper extremity.
  2. Wrist Pressure Gauge - The pressure gauge cuff is placed on the wrist.

How do I choose the right blood pressure monitor? Which one is the most accurate?

Mechanical pressure gauges are the most accurate gauges. If you know how to use them correctly, be sure not to choose another option for measuring pressure.

However, mechanical pressure gauges are not for everyone. They require the simultaneous use of a phonendoscope and also its correct operation.

It is also important to be able to take the correct reading based on the start and stop of the pulsating sound heard during the measurement in the phonendoscope tubes.

Digital pressure gauges are less accurate and the pressure measurement is affected by multiple factors.

The good news is that they are constantly undergoing technical developments that aim not only to make them more comfortable for the patient to use, but also to eliminate errors.

International standards and protocols have been developed to verify their accuracy and serve as a check on technical standards and parameters.

Interesting:
Before buying a blood pressure monitor, be sure to check whether the device has been verified by one of the international standards (certificate). The most well-known companies that verify the technical parameters of the device are, for example, IP EHS, CEN, DIN, or the protocol of the German League against Arterial Hypertension.

How to use the blood pressure monitor correctly?

Every single pressure measuring device purchased has an instruction manual in the package, as well as an explanation of the basic parameters of the particular device.

There you will also find the basic mistakes that patients make when using a blood pressure monitor, or what to avoid, what is absolutely incorrect.

An important piece of information that you will also find in the leaflet is information on the time and method of calibration

How to measure pressure with a mercury blood pressure monitor?

  • Do not exert yourself physically before taking the measurement
  • Sit comfortably and stay still for a while
  • Expose the part of your body where you will measure the pressure (a thin layer of clothing is not a problem)
  • Relax completely
  • Keep your legs down, do not cross them
  • Place the cuff on the shoulder, about 2 cm above the elbow socket
  • Put the olives of the phonendoscope in your ears
  • Check that the phonendoscope is set correctly by gently tapping on the eardrum
  • If you do not hear anything, turn the phonendoscope drum the other way round
  • Place the eardrum of the phonendoscope against the elbow so that the diaphragm faces downwards
  • Gently hold the top of the drum with your thumb to keep it in place during the measurement
  • With the other hand, close the valve located on the balloon
  • Repeatedly squeeze the balloon of the pressure gauge until the mercury level in the column is at the desired value
  • The desired value is a slightly higher value than your normal upper pressure
  • The gauge cuff gradually inflates as you squeeze the balloon
  • After inflating the cuff, slowly release the valve on the balloon
  • Follow the dial along the mercury column, the mercury gradually drops
  • When you hear a pulsing sound in the phonendoscope, read the first value (e.g. 135)
  • When you stop hearing a pulsating sound in the phonendoscope, read the second value (e.g. 85)
  • When the sound disappears, you can release the valve completely, the cuff will blow out
  • The value of the measured pressure is read based on the onset and cessation of the pulsation, i.e. the resulting pressure is 135/85

How to measure pressure with an aneroid pressure gauge?

  • Do not perform any physical exertion before measurement
  • Sit comfortably and remain still for a while
  • Expose the part of your body where you will measure the pressure (a thin layer of clothing is not a problem)
  • Relax completely
  • Keep your legs down, do not cross them
  • Place the cuff on the shoulder, about 2 cm above the elbow socket
  • Put the olives of the phonendoscope in your ears
  • Check that the phonendoscope is set correctly by gently tapping on the eardrum
  • If you do not hear anything, turn the phonendoscope drum the other way round
  • Place the eardrum of the phonendoscope against the elbow so that the diaphragm faces downwards
  • Gently hold the top of the drum with your thumb so that it stays in place during the measurement
  • With your other hand, close the valve located on the balloon
  • Repeatedly squeeze the balloon of the pressure gauge until the dial needle is at the desired value
  • The desired value is slightly higher than your normal upper pressure
  • The gauge cuff gradually inflates as you squeeze the balloon
  • After the cuff has inflated, slowly release the valve on the balloon
  • Watch the dial on the clock, the hand of the clock gradually decreases
  • When you hear a pulsating sound in the phonendoscope, read the first value (e.g. 135)
  • When you stop hearing the pulsating sound in the phonendoscope, read the second value (e.g. 85)
  • When the sound disappears, you can release the valve completely, the cuff will blow out
  • The value of the measured pressure is read based on the onset and cessation of the pulsation, i.e. the resulting pressure is 135/85

How to measure pressure with a digital arm pressure gauge?

  • Do not perform any physical exertion before measurement
  • Make sure you have batteries in the device or that it is plugged into the mains
  • Sit comfortably and stay still for a while
  • Expose the part of your body where you will measure the pressure (a thin layer of clothing is not a problem)
  • Relax completely
  • Keep your legs down, do not cross them
  • Place the cuff on the shoulder, about 2 cm above the elbow socket
  • Switch on the pressure gauge with the button provided
  • Switch on the start button on the pressure gauge to start the measurement
  • During the measurement, be calm, do not move, do not talk
  • The instrument alarms the end of the measurement with an audible signal and by releasing air from the cuff
  • Read the pressure value from the display

How to measure pressure with a digital wrist pressure gauge?

  • Do not exert yourself physically before taking the measurement
  • Make sure you have batteries in the device or that it is plugged into the mains
  • Sit comfortably and stay still for a while
  • Expose the part of your body where you will measure the pressure (a thin layer of clothing is not a problem)
  • Relax completely
  • Keep your legs down, do not cross them
  • Place the cuff about 2.5 cm above the wrist
  • Place the hand on which the measurement is to be taken higher up, at about heart level
  • Switch on the blood pressure monitor using the button provided
  • Switch on the start button on the blood pressure monitor to start the measurement
  • Be still, do not move, do not talk during the measurement
  • The device alarms the end of the measurement with an audible signal and by releasing the air from the cuff
  • Read the pressure value from the display

Home blood pressure measurement - principles and biggest mistakes

Home blood pressure measurement has become commonplace. A blood pressure monitor is found in almost every normal household and is commonplace for a hypertensive or cardiac patient.

Older patients who have multiple diseases or their health is not stable even have recorders with a thorough record of the values at regular time intervals.

Blood pressure monitors even archive the last measurement in memory (the number of measurements stored depends on the specific blood pressure monitor).

The advantage of home measurement is the convenience in the home environment without the need to visit a doctor and the time-saving.

In addition, at the doctor's office many patients are stressed, and the measured values can be 10 to 20 torr higher.

In patients with white coat syndrome, it tends to be even more, so measurements in your doctor's office may not be relevant.

Interesting:
It is rare that a patient's blood pressure is fine at the doctor's office, but the readings taken at home are borderline or high.
The danger is that such masked hypertension is very well overlooked for a long time.
It puts the patient at risk by ignorance of his diagnosis and late treatment.
Untreated hypertension is often the cause of acute myocardial infarction, stroke, pulmonary embolism, cerebral aneurysm, cerebral hemorrhage, and other serious life-threatening diseases.

When is it appropriate to measure blood pressure?

Blood pressure should be measured 3 times a day, especially in patients who take blood pressure medication in the morning, noon and evening.

For those who take medication only in the morning, or morning and evening, measuring 2 times a day is sufficient. It is done in the morning after waking up and in the evening before going to bed (before taking your dose).

Morning measurements should be taken shortly after waking. Higher pressure readings should be expected.

This is due to the fact that the last pressure medication taken has already flushed out of the body and it is necessary to take the morning dose.

This should ensure that it falls and is maintained at physiological values during the day.

The effect of the medication can be checked by measuring the patient before taking the medication and then one hour after taking the medication.

Just one hour after taking the medication, it is already absorbed and fully effective.

Principles of blood pressure measurement

The European Council on Arterial Hypertension recommends that blood pressure should be measured regularly 3 times a day, twice consecutively at an interval of about 2 minutes in unstable patients, and twice a week in stable patients.

Blood pressure measurement is also recommended if the patient feels unwell, experiencing symptoms that alarm a rise or fall in blood pressure, such as headache, dizziness, blurring before the eyes, collapse, hot flushes, chest pressure, palpitations or difficulty breathing.

It should always be performed at approximately the same time interval on the same limb. It is also important to use the device correctly.

Interesting:
Never measure pressure when your bladder is full.
It will be higher.

The biggest mistakes when measuring blood pressure

Many mistakes are often made when measuring blood pressure by lay people.

They are caused by people's lack of awareness of the measuring device, of the physiological values of the pressure being measured, and of situations and conditions where the pressure may not be within the normal range, even if it does not immediately imply pathology.

Most common errors:

  • weak or dead batteries
  • incorrect wiring of the instrument
  • failure to control the pressure measurement
  • incorrect cuff loading (space, loose cuff)
  • measurement through clothing
  • limb pinched by a rolled-up sleeve
  • measurement after exertion
  • measurement under stress
  • moving, talking during measurement
  • continuous pressure measurement

Important information at the end

When the pressure is high or low, with or without certain symptomatology, repeat the measurement 2 to 3 times. This eliminates a possible error of the device.
If the following measurement values are the same, the instrument measures well.
The measurement can also be verified on a family member without difficulties, where a normal pressure value is assumed.
In the event of a pathological pressure value, contact your doctor for a treatment consultation.
Only he or she can recommend the addition of a medication outside the normal daily dose.
Never prescribe medication yourself!
Our experience with patients who have tried to cure themselves is not always positive.
Interesting and incomprehensible in practice:
Often patients prescribe themselves a medicine that is not intended to treat high blood pressure. Or they are prescribed it by inexperienced relatives.
In practice, these are mainly heart medications (nitroglycerin, digoxin, antiarrhythmics), psychiatric medications (frontin, diazepam, lexaurin, xanax), pain medications (ataralgin, tramal) and others.
Taking the wrong medicine can lead to serious damage to health (heart rhythm disturbances, cardiac failure, severe hypotension, shock, collapse)
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The aim of the portal and content is not to replace professional examination. The content is for informational and non-binding purposes only, not advisory. In case of health problems, we recommend seeking professional help, visiting or contacting a doctor or pharmacist.