Measurement Procedure; Before Measurement; Common Sources Of Error - Microlife BP3AQ-1 Manual De Instrucciones

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 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 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 cush-
ion for support if necessary.
• If the arm artery lies considerably lower or higher than the heart, an erro-
neously high or low blood pressure will be measured. Each 15 cm (6") dif-
ference 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 permissi-
ble 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 in order to allow the accumulated blood to
flow away.
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