Blood Pressure: How To Measure and Read Correctly
It may seem that measuring blood pressure is a piece of cake, but most people do it incorrectly and therefore get incorrect results.
Dr. Alex
cardiovascular surgeon
How to measure
A mechanical tonometer is the most accurate method. However, to measure blood pressure (BP) by "mechanics" you need a second person with medical education and knowledge of the Korotkov method.
An automatic or semi-automatic electronic tonometer with a shoulder cuff is the most suitable self-measurement method to do at home. It’s accurate for 5–10 mm Hg, which is considered acceptable. However, electronic blood pressure monitoring with a wrist cuff distorts the result up to 30 mm Hg, since many people have a thin radial artery.
How to measure correctly
- Avoid stressful situations 20–30 minutes before the measurement, and sit quietly for 5 minutes before the procedure itself.
- Do not smoke or drink strong coffee or tea for 60 minutes before the procedure.
- Before measuring, do not use medicines with adrenostimulants, such as vasoconstrictor drops.
- If the arm circumference exceeds 33 cm, use a tonometer with a special wide cuff.
- When measuring, sit up straight on a chair with your legs in front of you, and rest your arm on the table at heart level.
- If blood pressure is found to be increased, it is necessary to repeat the procedure 3 times, waiting 3–5 minutes between attempts.
- It is necessary to measure the pressure on both arms — typically the difference in the readings should not exceed 10 mm Hg.
Whitecoat syndrome
Whitecoat syndrome happens with people who experience a sudden increase in blood pressure due to the fact they are about to have their blood pressure taken. This is typical for people with a labile nervous system and vegetative-vascular dystonia. Therefore, blood pressure measurements when taken at the doctor's office may be higher than when taken at home.
What the numbers say
Each age range has its own blood pressure indicators, but there are generally accepted norms for a healthy adult.
These are the two main indicators:
- Systolic, upper — the force of resistance of the vascular walls during the ejection of blood at the moment of compression of the heart muscle.
- Diastolic, lower — blood pressure on the walls of the arteries at the time of relaxation of the heart.
The American Heart Association and the European Heart Society have adopted the following blood pressure standards:
- Optimal — up to 120/80
- Increased normal — up to 130/80
- Hypertension I degree — from 140/90
- Hypertension II degree — from 150/90
- Hypertensive crisis — from 180/90 and above
What to do
Most hypertensive patients do not experience unpleasant symptoms, only finding that they have high blood pressure when they visit a doctor. Increased blood pressure erodes the body from the inside: the heart, brain, kidneys, and blood vessels all suffer from increased pressure.
Blood pressure above 130/80 mm Hg — arterial hypertension — isn’t considered a disease.
Doctors recommend daily monitoring of blood pressure to see if patients really suffer from hypertension. Daily monitoring also can eliminate causes of increased blood pressure. To assess how increases in blood pressure affect the body, doctors will order examinations of the heart (ECG, echocardiography), kidneys (urinalysis, blood test for creatinine), and blood vessels (ultrasound).
A change in lifestyle allows you to normalize blood pressure without drugs in 30–40 % of cases. You can do so by avoiding smoking and alcohol, losing weight, exercising more, and consuming under 5g of salt per day.
08 June 2021