Minimize Blood Pressure Reading Inaccuracy with Proper Technique

Blood pressure measurement technique errors — even something as simple as placing the cuff over clothing during measurement — can lead to noticeable inaccuracies in the blood pressure reading itself.

It’s that time of year again in Central New York. The home to Hillrom Front Line Care is in the midst of unpredictable Spring weather, where daily temperature swings mean your patients are wearing anything from a thick down parka to a light windbreaker at their next appointment. Whatever the garment of choice, it’s important to remember how clothing over the arm and other factors can affect your ability to obtain an accurate blood pressure reading.

While several factors can cause measurement errors, procedure-related errors — either from the blood pressure measurement device, or the person using the device — are often the most concerning.

The most common procedural errors in clinical practice include: ^{1, 2}

• Failure to allow for a rest period
• Talking with your patient during or immediately before taking a recording
• Improper patient positioning
• Incorrect cuff sizing
• Incorrect cuff inflation and deflation
• Failure to detect Korotkoff sounds
• And transcription errors

Those procedural errors may sound familiar and can be relatively simple to correct if you keep technique in mind. Some errors, however, may be more subtle. For example, the measurement phenomenon known as “terminal digit preference” results in many blood pressure readings ending in either a 0 or a 5, thus leading to an inaccurate measurement.^{3, 4} This practice of rounding up or down occurs in more than 50% of manual blood pressure readings, reducing the precision of the reading and the accuracy of a hypertension diagnosis.⁵

The overall impact of these technique errors in a single office visit can lead to noticeable inaccuracies in the blood pressure reading itself. Capturing a blood pressure reading with the usual outpatient blood pressure measurement technique is higher than blood pressure readings obtained using the recommended guideline technique. The potential consequence? Many patients diagnosed with hypertension might be normotensive, while others with true hypertension may be left undiagnosed.³

Understanding the Impact of Blood Pressure Measurement Errors on Blood Pressure Readings¹

It may seem simple, but remembering proper blood pressure measurement techniques is crucial for a more accurate reading — so make sure to have your patients remove that winter coat next time.