5. Measurement procedure
Please note: You should always be seated before and during
measurement.
5.1. Before measurement:
• Avoid eating and smoking as well as all forms of exertion directly before
measurement. These factors influence the measurement result. Find time
to relax by sitting in an armchair in a quiet atmosphere for about ten
minutes before your measurement.
• Remove any garment that fits closely to your upper arm.
• Always measure on the same arm (normally left).
• Compare measurements at the same time of day, since blood pressure
changes during the course of the day (as much as 20–40 mmHg).
5.2. Common sources of error
Note: Comparable blood pressure measurements always require
the same conditions. Conditions should always be quiet.
• All efforts by the user to support the arm can increase blood pressure.
Make sure you are in a comfortable, relaxed position and do not flex
any of the muscles in the measurement arm during the measurement.
Use a cushion for support if necessary.
• If the arm artery lies considerably lower or higher than the heart, an
erroneously high or low blood pressure will be measured. Each 15 cm
(6”) difference in height between your heart and the cuff results in a
measurement error of 10 mmHg.
• Cuffs that are too narrow or too short result in false measurement
values. Selecting the correct cuff is extremely important. Cuff size is
dependent upon the circumference of the arm (measured in the center).
The permissible range is printed on the cuff. If this is not suitable for
your use, please call 1-800-568-4147.
• A loose cuff or a sideways protruding air pocket causes false measure-
ment values.
• With repeated measurements, blood accumulates in the arm, which can
lead to false results. Consecutive blood pressure measurements should
be repeated after a 1 minute pause or after your arm has been held up
in order to allow the accumulated blood to flow away.
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