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
measurement.
• Remove any garment that fits closely to your upper arm.
• Always measure on the same arm (normally left).
• Always perform measurements at the same time of day, since blood pressure changes
during the course of the day.
5.2. Common sources of error:
Note: Comparable blood pressure measurements always require the same con-
ditions! 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 meas-
urement 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 15cm (6 inch) 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 contact microlife USA. Large cuff sizes are sold separately.
Note: Only use clinically approved microlife Cuffs!
• 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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