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5. Carrying out a Measurement
5.1. Before the measurement
• Avoid eating, smoking as well as all forms of exertion directly before the measurement. All these
factors influence the measurement result. Try to find time to relax by sitting in an armchair in a quiet
atmosphere for about 5 minutes before measurement.
• Remove any garment that fits closely to your upper arm.
• Always measure on the same arm (normally left).
• Take measurements regularly 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 conditions!
These are normally always quiet conditions.
• All efforts by the patient to support their arm can increase blood pressure. Make sure you are in a
comfortable, relaxed position and do not activate 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 (higher) than the heart, an false reading will be obtained. Each
15 cm difference in height 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
of extraordinary importance. The 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 your dealer.
Note: Only use clinically approved 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 the arm
has been held up in order to allow the accumulated blood to flow away.
5.3. Fitting the cuff
a) Push the cuff over the left upper arm so that the tube
points in the direction of the lower arm.
b) Lay the cuff on the arm as illustrated. Make certain that the
lower edge of the cuff lies approximately 2 to 3 cm above the
elbow and that the rubber tube leaves the cuff on the inner side
of the arm.
c) Tighten the free end of the cuff and close the cuff with the
closer.
d) The cuff should be snug on your upper arm, but not too tight. Any
clothing which restricts the arm (e.g. pullover) must be taken off.
e) Lay your arm on a table (palm upwards) so that the cuff is at the
same height as the heart. Make sure that the tube is not kinked.
2–3 cm
tube
