How to Determine “Real” Average Blood Pressure

Self monitoring is now recognized as more accurate than clinical measurements for a few reasons. First, people are more relaxed which eliminates white coat syndrome. Second, results from several studies have demonstrated that routine manual measurements by medical professionals are often innacurate.1 Third, home measuring provides lots of high quality data which are more representative of the real state of a persons blood pressure.

To determine ones “real average” blood pressure, measure 4 times a day at set times, for 7 consecutive days.

Readings 1 & 2
Take two readings (60 seconds apart) in the morning before breakfast or coffee, after the bladder has been emptied.

Readings 3 & 4
Take two additional readings in the evening (60 seconds apart), two hours after dinner and at least 30 minutes after exercise, smoking, or ingesting alcohol or caffeine.

How to Take BP Properly:

1. Relax for 5 minutes before taking measurements.
2. Do not move or speak during the measurement
3. Keep feet flat on the floor and legs uncrossed
4. Ensure the back is supported (use a chair and lean back)
5. Keep the arm supported (on a kitchen table for instance)
6. The cuff should be at heart level (use a pillow to lift if necessary)

A patient’s real average blood pressure is based on the average of all systolic numbers, and diastolic values, averaged separately, without the first day’s data. This “7 Day Protocol” is the gold standard for measuring BP accurately and is in guidelines for Home Monitoring as outlined by Hypertension Canada, the American Heart Association, and the European Hypertension Society.

Source:

1. Canadian Journal of Cardiology 2015 Vol 31, p620-630