BIOS BD201 - B Common Sources of Error; C Fitting the Wide Range Cuff

• Attempttocarryoutthemeasurementsregularlyatthesametimeofday,sincebloodpressurechangesduring
the course of the day. The ideal time to measure your blood pressure is in the morning after you wake up,
before breakfast and physical activity, and in the absence of the urge to urinate.
• Restfor5minutessittingquietlyandreleaseallthetensioninyourbody—especiallythearmmuscles—before
beginning with the measurement. Remain calm and quiet when the measurement is in process. Do not speak
or move your arm (as well as other body) muscles during the process.
• Ideally,youwillbesittingatatablewithbothfeetontheoor,andyourarmrestingonthetablewiththecuff
at heart level.
3.3B Common Sources of Error
All efforts by the patient to support the arm can increase the 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.
ATTENTION!
Comparable blood pressure measurements always require the same conditions with a peaceful and
calm environment. Ensure that you take measurements under the same conditions to obtain an
accurate estimate of blood pressure variation patterns.
• Ifthearmarteryliesconsiderablylowerorhigherthantheheart,anerroneousvalueofbloodpressureis
measured. Each 15 cm difference in height results in a measurement error of 10 mmHg.
• Aloosecuff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 at least a 15 second pause or after the arm has been
held up in order to allow the accumulated blood to flow away.
3.3C Fitting the Wide Range Cuff
a) Put the end of the cuff (with fastener) through the metal ring, making
the cuff a cylinder. (Ignore this step if your cuff is already set up.)
Proper assembly allows the Velcro
®
to match up properly.
b) Place the cuff around your arm. Make sure the bottom edge of the
cuff is about 1” (2-3 cm) above the elbow joint. Adjust the cuff so that
the rubber tubing under the cuff lies over the brachial artery, which
runs on the inside of the arm (see Fig. B). The red material should be
over the braechial artery.
c) Pull the cuff and tighten it by attaching the Velcro
®
fastener. Normally,
the left arm is used, unless there is a physical reason for using the
right arm.
a)
b)
c)