Welch Allyn Vital Signs Monitor - User Manual - Manual (Page 50)

44 Vital Signs Monitor
General Guide to Problems and Corrective Actions
Symptom Possible Cause Explanations and Corrective Action
1 Inaccurate Blood
Pressure Readings
Please Note:
Differences of up to 10mmHg is
considered normal and will occur
for a number of reasons includ-
ing intrapatient BP variability,
observer hearing differences,
and ausultatory deflation rate.
Incorrect cuff size
NOTE: Use Welch Allyn
approved cuffs only.
Determine correct cuff size:
•
Use reference markings on cuff
• Measure patient’s arm circumference midway
between elbow and shoulder (see
“Chart for
Determining Cuff Size” on page 27 of Opera-
tor’s Manual to select correct cuff size).
Patient’s arm position Ensure patient’s arm is at heart level.
Arm movement during
blood pressure cycle Keep arm still during blood pressure cycle:
•
Movement may cause inaccuracies from arti-
fact.
Blood pressure taken over
clothing Blood pressure should be taken on a bare arm.
Arrhythmia Check for regularity of heart rate:
(palpate pulse or check monitor)
• Moderate to severe heart rate irregularities
may make blood pressure difficult to measure.
Incorrect reference Use the correct Korotkoff sound to determine
diastolic blood pressure.
•
Many listeners incorrectly equate diastolic
blood pressure with the disappearance of
sound only (phase 5). The Welch Allyn Vital
Signs Monitor was developed using the Ameri-
can Heart Association recommendations,
which state that phase 5 be used unless sound
continues to 0 mmHg, in which case the
change in the quality of sound (phase 4) is to
be used.
Deflate cuff no faster than 3 mmHg per second:
•
One of the major sources of error in ausculta-
tory blood pressure measurement is deflating
the cuff too quickly. The American Heart Asso-
ciation recommends deflation no faster than 3
mmHg per second.
Only use a sphygmomanometer that is known
to be in calibration:
•
Blood pressure taken with an un-calibrated
sphygmomanometer may be very inaccurate.
Change in blood pressure
from auscultatory reading
to Welch Allyn Vital Signs
Monitor reading Check blood pressure immediately prior to
Welch Allyn Vital Signs Monitor Reading.
Poor auscultatory sound
recognition by observer Use higher quality stethoscope. Have a differ-
ent observer check patient’s blood pressure.