Microlife BP3NC1-1W, Instruction Booklet

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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 the arm can increase blood pres-
sure. Make sure you are in a comfortable, relaxed position and do not
activate any of the muscles in the measurement arm during the mea-
surement. Use a cushion for support if necessary.
• If the wrist artery lies considerably lower (higher) than the heart, an
erroneously higher (lower) blood pressure will be measured! (Each
15cm/6" difference in height results in a measurement error
of10mmHg!)
• A loose cuff causes false measurement values.
• With repeated measurements, blood can accumulate in the respective
arm, which can lead to false results. Correctly executed blood pressure
measurements should therefore first be repeated after a 1 minute
pause or after the arm has been held up in order to allow the accumu-
lated blood to flow away.
5.3. Fitting the cuff
a) Remove all objects and jewelry (e.g.
wristwatch) from the wrist in use. Put the
cuff over the wrist with the monitor face
on the inside of the wrist.
b) The distance between the cuff and the
hand should be approx. 10 mm (1/2").
c) Secure the cuff with the Velcro fastener,
so that it lies comfortably and not too
tight. No space should remain between
the cuff and the wrist.
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