Proper Technique for Blood Pressure Measurement

Is your blood pressure being measured correctly? Accurate blood pressure measurements are essential for diagnosing and treating high blood pressure. A specific set of techniques and procedures have been developed for obtaining the most accurate blood pressure readings possible.

But research has shown that medical professionals often do not completely follow these guidelines. It is important for you as a patient to be able to identify when proper protocol is being followed, or not.

1

When to Measure

Doctor measuring patients Blood Pressure

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It is normal to see a small amount of blood pressure fluctuation during different times of the day. Taking multiple measurements corrects for these daytime fluctuations, but there are some special timing issues that should be addressed.

The American Heart Association says that your blood pressure should be measured under controlled circumstances to get a truly accurate reading. You should be sitting in a chair with a back support and with your feet on the floor. (Sitting on an exam table with your feet dangling is insufficient.) You should sit quietly without talking or interacting for at least five minutes. Obviously, many blood pressure readings made in a healthcare provider's office will not meet these criteria. Nonetheless, you should know that a diagnosis of hypertension should not be made unless your healthcare provider has taken these steps to assure a truly baseline blood pressure measurement.

2

Choose the Proper Cuff Size

Doctor measuring patients blood pressure

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One of the most important factors that can influence the accuracy of blood pressure readings is the size of the blood pressure cuff that is used. There is a very specific set of guidelines for precise cuff sizing. But it can be difficult for patients to tell, just by looking, if their healthcare provider is using a correctly sized cuff.

If you are significantly above or below "average" height or weight, then the healthcare provider or nurse should probably not be using the cuff that is already in the room. The "default" cuff that is usually kept in the examining room is meant to be used for average sized people, and will not produce an accurate reading if you are larger or smaller than average.

The official guidelines specify the following cuff sizes:

  • Arm circumference 22 to 26 cm, 'small adult' cuff, 12 x 22 cm
  • Arm circumference 27 to 34 cm, 'adult' cuff: 16 x 30 cm
  • Arm circumference 35 to 44 cm, 'large adult' cuff: 16 x 36 cm
  • Arm circumference 45 to 52 cm, 'adult thigh' cuff: 16 x 42
3

Proper Positioning

Doctor checks man's blood pressure.

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Proper positioning is vital in obtaining accurate blood pressure readings.

In general, blood pressure should be measured while you are seated comfortably. The arm being used should be relaxed, uncovered, and supported at the level of the heart. Only the part of the arm where the blood pressure cuff is fastened needs to be at heart level, not the entire arm.

Sometimes your healthcare provider will take your blood pressure while you are reclined or while you are standing up. This is appropriate in certain cases, but he should also be measuring your blood pressure while you are positioned in the seated posture, as described above.

4

Multiple Readings Should Be Taken

Doctor examining patient in office

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One blood pressure reading is not enough to get an accurate measurement. While the specifics of how many readings are necessary can change based on many factors, the essential need for multiple measurements does not.

To ensure an accurate reading, your healthcare provider should be checking your blood pressure over time, and watching the how the values change between office visits. More than this, though, he should actually be taking your blood pressure more than once during each office visit.

Because things like temperature and stress can change blood pressure, more than one reading in a single office visit allows the ability to correct for these variations. For example, your blood pressure is often higher at the beginning of an office visit than at the end. Taking a reading at both the beginning and the end gives a more accurate average reading.

Your healthcare provider should be checking your blood pressure:

  • In both arms, not just one
  • At both the beginning and the end of your appointment
5

Expect Correct Technique

doctor checking senior man's blood pressure in a medical office

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There is no reason for you to expect your doctor or nurse to use anything less than perfect technique when measuring your blood pressure. If you see your healthcare provider making any mistakes or not following proper procedure, you should ask why. While variations on technique are sometimes necessary, he should be able to clearly explain these to you, or he should apologize for not following accepted procedure and start the measurement over.

You should also tell your healthcare provider if you have taken any medicines prior to your appointment, or if you have smoked, exercised, or eaten anything in the past hour—even if he doesn't ask.

Frequently Asked Questions

  • Which arm should be used to take blood pressure?

    Both arms should be used to take blood pressure. Measuring the blood pressure of each arm can help ensure an accurate test.

  • What is the best position to take blood pressure?

    Sit in a chair with back support and place your feet flat on the ground. Don't cross your legs. The arm being tested should be relaxed and the blood pressure cuff should be at heart level.

  • How do I measure blood pressure at home?

    To accurately measure your blood pressure at home, you will need a blood pressure monitor. There are many different types, but the American Heart Association recommends an automatic, cuff-style, upper-arm device. These are most similar to the equipment used in a doctor's office.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Kallioinen N, Hill A, Horswill MS, Ward HE, Watson MO. Sources of inaccuracy in the measurement of adult patients' resting blood pressure in clinical settings: a systematic review. J Hypertens. 2017;35(3):421-441. doi:10.1097/HJH.0000000000001197

  2. Irving G, Holden J, Stevens R, Mcmanus RJ. Which cuff should I use? Indirect blood pressure measurement for the diagnosis of hypertension in patients with obesity: a diagnostic accuracy review. BMJ Open. 2016;6(11):e012429. doi:10.1136/bmjopen-2016-012429

  3. American Heart Association (AHA). Monitoring your blood pressure at home.

By Craig O. Weber, MD
Craig O. Weber, MD, is a board-certified occupational specialist who has practiced for over 36 years.