Pronk Technologies SimCube, Operator'S Manual

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If this is the case you cannot use this method.
Neo Mode Simulation Setup
In a neonatal NIBP setup the patient cuff may
represent just a few ml of volume, while the
patient hose may represent 50 ml or more of
volume. Since the SimCube operates by pulse
volume (about 1/4 ml at peak in neo mode) the
pressure pulses can be much larger on single
lumen than on dual lumen systems. Some
single lumen systems do not have enough
dynamic range to reliably capture the pulses
produced by the SimCube with a #1 neo cuff.
While we have had good results with a #2 neo
cuff, we recommend using a loosely wrapped
#3 neo cuff for neonatal simulation on single
lumen systems. Dual lumen systems should
work reliably with a #1 neo cuff.
Due to the reduced pulse size of our neonatal
simulation many monitors will not be able take
readings on this simulation if the monitor is in
adult mode or if you are using an adult cuff. We
strongly recommend using a neonatal cuff and
placing the monitor in neonatal mode.
However, if you do not have access to a
neonatal cuff, any volume in the range to 15 to
75ml will work with most monitors. This can be
achieved with an infant cuff or, in some cases,
with a tightly rolled child cuff. Also, a length of
tubing can be used. A rough but handy
approximation is that a 1 inch length of 1/8 inch
I.D. tubing is around 1ml in volume.
Reading to Reading Variations
Even with the best setup there is still variation
from reading to reading. Sometimes a reading
will be produced which is quite far off target and
it is difficult to know if this represents a problem
with the monitor or not. The AAMI spec says
that 1% of readings can be as much as
29mmHg off, but under simulation, and using
the techniques we have described you should
see much less than that. The following chart
shows some typical error distributions. These
represent the difference from 120mmHg
systolic using SimCube's adult
mode with a 400ml Cuff, discarding the first
reading, for 50 readings. On some monitors
systolic and diastolic have similar error
distributions, while on others they are quite
different.
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MDE HP Critikon
<2mmHg
2-3mmHg
4-5mmHg
6-7mmHg
8-9mmHg
10+mmHg
About The Author
Karl Ruiter has been an engineer, a manager,
and a director at a Los Angeles-based medical
device manufacturer where he designed a
NIBP algorithm which is in use in tens of
thousands of units worldwide. This algorithm
has been shown by competing manufacturers
to be one of the most consistent and
noise-immune on the market. In 2003 he
helped to found Pronk Technologies Inc, which
bases its product line on the concept that
biomedical engineers do important work and
they should have really good tools. He was
the lead engineer on the SimCube product.
More Info
More information about the SimCube and
NIBP simulation can be found:
On the Web at: www.pronktech.com
By email at: sales@pronktech.com
By phone at: (800) 609-9802
Revision O 0 7/18/ 2017
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