Fluke Biomedical BP Pump 2 - Manual (Page 72)

BP Pump 2
Operators Manual
B-2
“The mean difference of the paired measurements of the test system and the
comparison system shall be ± 5 mmHg or less with a standard deviation of
8 mmHg or less.”
This means that variations in individual readings of 5, 6, or even 10 mmHg are
quite normal and do not indicate that either the DINAMAP or the Tester are
malfunctioning. Some monitors are more repeatable than others, and
repeatability is one measure of the overall quality of the monitor.
Q: BP results vary using the same preset pressure.
“I checked another NIBP monitor using the same preset simulated blood
pressure of 120/80 (93) with a pulse rate of 80 bpm. This time I got the
following results:
Trial # Systolic Mean Diastolic Pulse Rate
1 120 89 71 80
2 120 87 73 80
3 121 91 72 80
Why does this monitor show such low Diastolic pressures?”
A: Monitors using different references – Ascultatory vs. Invasive data.
Neither the monitor nor the Tester is broken or giving incorrect readings.
Some monitors were designed to give readings close to those obtained by the
Ascultatory method of blood pressure determination. Other monitors have been
designed to agree with Invasive Blood Pressure readings. It is well known that
Invasive and Ascultatory BP readings on the same subject can be quite
different. Therefore it is not surprising that automated Oscillometric NIBP
monitors using Invasive readings as a reference would give different readings
than a monitor based on Ascultatory readings.
Cuff Issues
Q: Why is an Internal Cuff used?
“Why does the Tester use an Internal Simulated Cuff? Wouldn’t it be better to
include a real cuff in the measurement?”
A: Internal Cuff produces accurate and repeatable simulations.
The Tester uses an internal cuff to help ensure accurate and repeatable
simulations over time. The internal “cuff” is a 310-ml fixed volume that has
compliance very nearly equal to a normal adult cuff when used at typical adult