4. How do I take a measurement?
Please note: You should always be seated before and during
measurement.
4.1. Preparing to take a 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 5 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 mm Hg).
4.2. Common errors
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 mm Hg.
• 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
measurement 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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